Enzyme Inhibitors

ABSTRACT

Compounds of formula (I) are inhibitors of histone deacetylase activity, and are useful in the treatment of, for example, cancers, wherein R 1  is a carboxylic acid group (—COOH), or an ester group which is hydrolysable by one or more intracellular carboxyesterase enzymes to a carboxylic acid group; R 2  is the side chain of a natural or non-natural alpha amino acid; Y is a bond, C(═O)—, —S(═O) 2 —, —C(—O)O—, —C(O)NR 3 —, —C(═S)—NR 3 , —C(═NH)NR 3  or —S(═O) 2 NR 3 — wherein R 3  is hydrogen or optionally substituted C 1 -C 6  alkyl; L is a divalent radical of formula -(Alk 1 ) m (O) n (Alk 2 ) p — wherein m, n and p are independently 0 or 1, Q is (i) an optionally substituted divalent mono- or bicyclic carbocyclic or heterocyclic radical having 5-13 ring members, or (ii), in the case where both m and p are 0, a divalent radical of formula —X 2 -Q 1 - or -Q 1 -X 2 — wherein X 2  is —O—, S— or NR A — wherein R A  is hydrogen or optionally substituted C 1 -C 3  alkyl, and Q 1  is an optionally substituted divalent mono- or bicyclic carbocyclic or hetero-cyclic radical having 5-13 ring members, AIk 1  and AIk 2  independently represent optionally substituted divalent C 3 -C 7  cycloalkyl radicals, or optionally substituted straight or branched, C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene radicals which may optionally contain or terminate in an ether (—O—), thioether (—S—) or amino (—NR A -) link wherein R A  is hydrogen or optionally substituted C 1 -C 3  alkyl; X represents a bond; —C(═O); or —S(═O) 2 —; —NR 4 C(═O)—, —C(═O)NR 4 —, —NR 4 C(═O)NR 5 —, —NR 4 S(═O) 2 —, or —S(═O) 2 NR 4 — wherein R 4  and R 5  are independently hydrogen or optionally substituted C 1 -C 6  alkyl; z is 0 or 1; A represents an optionally substituted mono-, bi- or tri-cyclic carbocyclic or heterocyclic ring system wherein the radicals R 1 R 2 NH—Y-L 1 -X 1 —[CH 2 ] z — and HONHCO-[LINKER]- are attached different ring atoms; and -[Linker]- represents a divalent linker radical linking a ring atom in A with the hydroxamic acid group CONHOH, the length of the linker radical, from the terminal atom linked to the ring atom of A to the terminal atom linked to the hydroxamic acid group, is equivalent to that of an unbranched saturated hydrocarbon chain of from 3-10 carbon atoms.

This invention relates to compounds which inhibit members of the histonedeacetylase family of enzymes and to their use in the treatment of cellproliferative diseases, including cancers, polyglutamine diseases, forexample Huntingdon disease, neurodegenerative diseases for exampleAlzheimer disease, autoimmune disease for example rheumatoid arthritisand organ transplant rejection, diabetes, haematological disorders,inflammatory disease, cardiovascular disease, atherosclerosis, and theinflammatory sequelae of infection.

BACKGROUND TO THE INVENTION

In eukaryotic cells DNA is packaged with histones, to form chromatin.Approximately 150 base pairs of DNA are wrapped twice around an octamerof histones (two each of histories 2A, 2B, 3 and 4) to form anucleosome, the basic unit of chromatin. The ordered structure ofchromatin needs to be modified in order to allow transcription of theassociated genes. Transcriptional regulation is key to differentiation,proliferation and apoptosis, and is, therefore, tightly controlled.Control of the changes in chromatin structure (and hence oftranscription) is mediated by covalent modifications to histones, mostnotably of the N-terminal tails. Covalent modifications (for examplemethylation, acetylation, phosphorylation and ubiquitination) of theside chains of amino acids are enzymatically mediated (A review of thecovalent modifications of histones and their role in transcriptionalregulation can be found in Berger S L 2001 Oncogene 20, 3007-3013; SeeGrunstein, M 1997 Nature 389, 349-352; Wolffe A P 1996 Science 272,371-372; and Wade P A et al 1997 Trends Biochem Sci 22, 128-132 forreviews of histone acetylation and transcription).

Acetylation of histones is associated with areas of chromatin that aretranscriptionally active, whereas nucleosomes with low acetylationlevels are, typically, transcriptionally silent. The acetylation statusof histones is controlled by two enzyme classes of opposing activities;histone acetyltransferases (HATs) and histone deacetylases (HDACs). Intransformed cells it is believed that inappropriate expression of HDACsresults in silencing of tumour suppressor genes (For a review of thepotential roles of HDACs in tumorigenesis see Gray S G and Teh B T 2001Curr Mol Med 1, 401-429). Inhibitors of HDAC enzymes have been describedin the literature and shown to induce transcriptional reactivation ofcertain genes resulting in the inhibition of cancer cell proliferation,induction of apoptosis and inhibition of tumour growth in animals (Forreview see Kelly, W K et al 2002 Expert Opin Investig Drugs 11,1695-1713). Such findings suggest that HDAC inhibitors have therapeuticpotential in the treatment of proliferative diseases such as cancer(Kramer, O H et al 2001 Trends Endocrinol 12, 294-300, Vigushin D M andCoombes R C 2002 Anticancer Drugs 13, 1-13).

In addition, others have proposed that aberrant HDAC activity or histoneacetylation is implicated in the following diseases and disorders;polyglutamine disease, for example Huntingdon disease (Hughes R E 2002Curr Biol 12, R141-R143; McCampbell A et al 2001 Proc Soc Natl Acad Sci98, 15179-15184; Hockly E et al 2003 Proc Soc Natl Acad Sci 100,2041-2046), other neurodegenerative diseases, for example Alzheimerdisease (Hempen B and Brion J P 1996, J Neuropathol Exp Neurol 55,964-972), autoimmune disease and organ transplant rejection (Skov S etal 2003 Blood 101, 14 30-1438; Mishra N et al 2003 J Clin Invest 111,539-552), diabetes (Mosley A L and Ozcan S 2003 J Biol Chem 278,19660-19666) and diabetic complications, infection (including protozoalinfection (Darkin-Rattray, S J et al 1996 Proc Soc Natl Acad Sci 93,13143-13147)) and haematological disorders including thalassemia (Witt Oet al 2003 Blood 101, 2001-2007). The observations contained in thesemanuscripts suggest that HDAC inhibition should have therapeutic benefitin these, and other related, diseases

Many types of HDAC inhibitor compounds have been suggested, and severalsuch compounds are currently being evaluated clinically, for thetreatment of cancers. For example, the following patent publicationsdisclose such compounds:

U.S. Pat. No. 5,369,108 and WO 03/076395 WO 04/110989 WO 01/18171 WO03/076400 WO 04/092115 U.S. Pat. No. 4,254,220 WO 03/076401 WO04/0224991 WO 01/70675 WO 03/076421 WO 05/014588 WO 01/38322 WO03/076430 WO 05/018578 WO 02/30879 WO 03/076422 WO 05/019174 WO 02/26703WO 03/082288 WO 05/004861 WO 02/069947 WO 03/087057 WO 05/007091 WO02/26696 WO 03/092686 WO 05/030704 WO 03/082288 WO 03/066579 WO05/013958 WO 02/22577 WO 03/011851 WO 05/028447 WO 03/075929 WO04/013130 WO 05/026907

Many of the HDAC inhibitors known in the art have a structural template,which may be represented as in formula (A):

wherein ring A is a carbocyclic or heterocyclic ring system withoptional substituents R, and [Linker] is a linker radical of varioustypes. The hydroxamate group functions as a metal binding group,interacting with the metal ion at the active site of the HDAC enzyme,which lies at the base of a pocket in the folded enzyme structure. Thering or ring system A lies within or at the entrance to the pocketcontaining the metal ion, with the -{Linker]- radical extending deeperinto that pocket linking A to the metal binding hydroxamic acid group.In the art, and occasionally herein, the ring or ring system A issometimes informally referred to as the “head group” of the inhibitor.

The use of prodrugs to enhance the delivery to target organs andtissues, or to overcome poor pharmacokinetic properties of the parentdrug, is a well known medicinal chemistry approach. Administration ofester prodrugs, for example, which are hydrolysed by serumcarboxylesterases in vivo to the active parent acids, can result inhigher serum levels of the parent acid than administration of the aciditself.

BRIEF DESCRIPTION OF THE INVENTION

This invention is based on the finding that the introduction of an alphaamino acid ester grouping into the HDAC inhibitor molecular template (A)above facilitates penetration of the agent through the cell membrane,and thereby allows intracellular carboxylesterase activity to hydrolysethe ester to release the parent acid. Being charged, the acid is notreadily transported out of the cell, where it therefore accumulates toincrease the intracellular concentration of active HDAC inhibitor. Thisleads to increases in potency and duration of action. The inventiontherefore makes available a class of compounds whose structures arecharacterised by having an alpha amino acid ester moiety which is asubstrate for intracellular carboxylesterase (also referred to herein asan “esterase motif”) covalently linked to an HDAC inhibitor moleculartemplate, and to the corresponding de-esterified parent acids, suchcompounds having pharmaceutical utility in the treatment of diseasessuch as cancers which benefit from intracellular inhibition of HDAC.

DETAILED DESCRIPTION OF THE INVENTION

According to the present invention there is provided a compound offormula (I) or a salt, N-oxide, hydrate or solvate thereof:

whereinR₁ is a carboxylic acid group (—COOH), or an ester group which ishydrolysable by one or more intracellular carboxylesterase enzymes to acarboxylic acid group;R₂ is the side chain of a natural or non-natural alpha amino acid;Y is a bond, —C(═O)—, —S(═O)₂—, —C(═O)O—, —C(═O)NR₃—, —C(═S)—NR₃,—C(═NH)NR₃ or —S(═O)₂NR₃— wherein R₃ is hydrogen or optionallysubstituted C₁-C₆ alkyl;L¹ is a divalent radical of formula -(Alk¹)_(m)(Q)_(n)(Alk²)_(p)—wherein

-   -   m, n and p are independently 0 or 1,    -   Q is (i) an optionally substituted divalent mono- or bicyclic        carbocyclic or heterocyclic radical having 5-13 ring members, or        (ii), in the case where both m and p are 0, a divalent radical        of formula —X²-Q¹- or -Q¹-X²— wherein X² is —O—, S— or NR^(A)—        wherein R^(A) is hydrogen or optionally substituted C₁-C₃ alkyl,        and Q¹ is an optionally substituted divalent mono- or bicyclic        carbocyclic or heterocyclic radical having 5-13 ring members,    -   Alk¹ and Alk² independently represent optionally substituted        divalent C₃-C₇ cycloalkyl radicals, or optionally substituted        straight or branched, C₁-C₆ alkylene, C₂-C₆ alkenylene, or C₂-C₆        alkynylene radicals which may optionally contain or terminate in        an ether (—O—), thioether (—S—) or amino (—NR^(A)—) link wherein        R^(A) is hydrogen or optionally substituted C₁-C₃ alkyl;        X¹ represents a bond; —C(═O); or —S(═O)₂—; —NR₄C(═O)—,        —C(═O)NR₄—, —NR₄C(═O)NR₅—, —NR₄S(═O)₂—, or —S(—O)₂NR₄— wherein        R₄ and R₅ are independently hydrogen or optionally substituted        C₁-C₆ alkyl;        z is 0 or 1;        A represents an optionally substituted mono-, bi- or tri-cyclic        carbocyclic or heterocyclic ring system wherein the radicals        R₁R₂NH—Y-L¹-X¹-[CH₂]_(z)— and HONHCO-[LINKER]- are attached        different ring atoms; and        -[Linker]- represents a divalent linker radical linking a ring        atom in A with the hydroxamic acid group —CONHOH, the length of        the linker radical, from the terminal atom linked to the ring        atom of A to the terminal atom linked to the hydroxamic acid        group, is equivalent to that of an unbranched saturated        hydrocarbon chain of from 3-10 carbon atoms.

Although the above definition potentially includes molecules of highmolecular weight, it is preferable, in line with general principles ofmedicinal chemistry practice, that the compounds with which thisinvention is concerned should have molecular weights of no more than600.

In another broad aspect the invention provides the use of a compound offormula (I) as defined above, or an N-oxide, salt, hydrate or solvatethereof in the preparation of a composition for inhibiting the activityof an HDAC enzyme.

The compounds with which the invention is concerned may be used for theinhibition of HDAC activity, particularly HDAC1 activity, ex vivo or invivo.

In one aspect of the invention, the compounds of the invention may beused in the preparation of a composition for the treatment ofcell-proliferation disease, for example cancer cell proliferation,polyglutamine diseases for example Huntingdon disease, neurodegenerativediseases for example Alzheimer disease, autoimmune disease for examplerheumatoid arthritis, and organ transplant rejection, diabetes,haematological disorders, infection (including but not limited toprotozoal and fungal), inflammatory disease, and cardiovascular disease,including atherosclerosis.

In another aspect, the invention provides a method for the treatment ofthe foregoing disease types, which comprises administering to a subjectsuffering such disease an effective amount of a compound of formula (I)as defined above.

The term “ester” or “esterified carboxyl group” means a groupR_(g)O(C═O)— in which R_(g) is the group characterising the ester,notionally derived from the alcohol R₉OH.

As used herein, the term “(C_(a)-C_(b))alkyl” wherein a and b areintegers refers to a straight or branched chain alkyl radical havingfrom a to b carbon atoms. Thus when a is 1 and b is 6, for example, theterm includes methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl,sec-butyl, t-butyl, n-pentyl and n-hexyl.

As used herein the term “divalent (C_(a)-C_(b))alkylene radical” whereina and b are integers refers to a saturated hydrocarbon chain having froma to b carbon atoms and two unsatisfied valences.

As used herein the term “(C_(a)-C_(b))alkenyl” wherein a and b areintegers refers to a straight or branched chain alkenyl moiety havingfrom a to b carbon atoms having at least one double bond of either E orZ stereochemistry where applicable. The term includes, for example,vinyl, allyl, 1- and 2-butenyl and 2-methyl-2-propenyl.

As used herein the term “divalent (C_(a)-C_(b))alkenylene radical” meansa hydrocarbon chain having from a to b carbon atoms, at least one doublebond, and two unsatisfied valences.

As used herein the term “C_(a)-C_(b) alkynyl” wherein a and b areintegers refers to straight chain or branched chain hydrocarbon groupshaving from two to six carbon atoms and having in addition one triplebond. This term would include for example, ethynyl, 1-propynyl, 1- and2-butynyl, 2-methyl-2-propynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl,2-hexynyl, 3-hexynyl, 4-hexynyl and 5-hexynyl.

As used herein the term “divalent (C_(a)-C_(b))alkynylene radical”wherein a and b are integers refers to a divalent hydrocarbon chainhaving from 2 to 6 carbon atoms, and at least one triple bond.

As used herein the term “carbocyclic” refers to a mono-, bi- ortricyclic radical having up to 16 ring atoms, all of which are carbon,and includes aryl and cycloalkyl.

As used herein the term “cycloalkyl” refers to a monocyclic saturatedcarbocyclic radical having from 3-8 carbon atoms and includes, forexample, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyland cyclooctyl.

As used herein the unqualified term “aryl” refers to a mono-, bi- ortri-cyclic carbocyclic aromatic radical, and includes radicals havingtwo monocyclic carbocyclic aromatic rings which are directly linked by acovalent bond. Illustrative of such radicals are phenyl, biphenyl andnapthyl.

As used herein the unqualified term “heteroaryl” refers to a mono-, bi-or tri-cyclic aromatic radical containing one or more heteroatomsselected from S, N and O, and includes radicals having two suchmonocyclic rings, or one such monocyclic ring and one monocyclic arylring, which are directly linked by a covalent bond. Illustrative of suchradicals are thienyl, benzthienyl, furyl, benzfuryl, pyrrolyl,imidazolyl, benzimidazolyl, thiazolyl, benzthiazolyl, isothiazolyl,benzisothiazolyl, pyrazolyl, oxazolyl, benzoxazolyl, isoxazolyl,benzisoxazolyl, isothiazolyl, triazolyl, benztriazolyl, thiadiazolyl,oxadiazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl,indolyl and indazolyl.

As used herein the unqualified term “heterocyclyl” or “heterocyclic”includes “heteroaryl” as defined above, and in its non-aromatic meaningrelates to a mono-, bi- or tri-cyclic non-aromatic radical containingone or more heteroatoms selected from S, N and O, and to groupsconsisting of a monocyclic non-aromatic radical containing one or moresuch heteroatoms which is covalently linked to another such radical orto a monocyclic carbocyclic radical. Illustrative of such radicals arepyrrolyl, furanyl, thienyl, piperidinyl, imidazolyl, oxazolyl,isoxazolyl, thiazolyl, thiadiazolyl, pyrazolyl, pyridinyl, pyrrolidinyl,pyrimidinyl, morpholinyl, piperazinyl, indolyl, morpholinyl,benzfuranyl, pyranyl, isoxazolyl, benzimidazolyl, methylenedioxyphenyl,ethylenedioxyphenyl, maleimido and succinimido groups.

Unless otherwise specified in the context in which it occurs, the term“substituted” as applied to any moiety herein means substituted with upto four compatible substituents, each of which independently may be, forexample, (C₁-C₆)alkyl, (C₁-C₆)alkoxy, hydroxy, hydroxy(C₁-C₈)alkyl,mercapto, mercapto(C₁-C₆)alkyl, (C₁-C₆)alkylthio, phenyl, halo(including fluoro, bromo and chloro), trifluoromethyl, trifluoromethoxy,nitro, nitrile (—CN), oxo, —COOH, —COOR^(A), —COR^(A), —SO₂R^(A),—CONH₂, —SO₂NH₂, —CONHR^(A), —SO₂NHR^(A), —CONR^(A)R^(B),—SO₂NR^(A)R^(B), —NH₂, —NHR^(A), —NR^(A)R^(B), —OCONH₂, —OCONHR^(A),—OCONR^(A)R^(B), —NHCOR^(A), —NHCOOR^(A), —NR^(B)COOR^(A), —NHSO₂OR^(A),—NR^(B)SO₂OH, —NR^(B)SO₂OR^(A), —NHCONH₂, —NR^(A)CONH₂, —NHCONHR^(B),—NRACONHR^(B), —NHCONR^(A)R^(B), or —NRACONR^(A)R^(B) wherein R^(A) andR^(B) are independently a (C₁-C₆)alkyl, (C₃-C₆) cycloalkyl, phenyl ormonocyclic heteroaryl having 5 or 6 ring atoms. An “optionalsubstituent” may be one of the foregoing substituent groups.

The term “side chain of a natural or non-natural alpha-amino acid”refers to the group R¹ in a natural or non-natural amino acid of formulaNH₂—CH(R¹)—COOH.

Examples of side chains of natural alpha amino acids include those ofalanine, arginine, asparagine, aspartic acid, cysteine, cystine,glutamic acid, histidine, 5-hydroxylysine, 4-hydroxyproline, isoleucine,leucine, lysine, methionine, phenylalanine, proline, serine, threonine,tryptophan, tyrosine, valine, α-aminoadipic acid, α-amino-n-butyricacid, 3,4-dihydroxyphenylalanine, homoserine, α-methylserine, ornithine,pipecolic acid, and thyroxine.

Natural alpha-amino acids which contain functional substituents, forexample amino, carboxyl, hydroxy, mercapto, guanidyl, imidazolyl, orindolyl groups in their characteristic side chains include arginine,lysine, glutamic acid, aspartic acid, tryptophan, histidine, serine,threonine, tyrosine, and cysteine. When R₂ in the compounds of theinvention is one of those side chains, the functional substituent mayoptionally be protected.

The term “protected” when used in relation to a functional substituentin a side chain of a natural alpha-amino acid means a derivative of sucha substituent which is substantially non-functional. For example,carboxyl groups may be esterified (for example as a C₁-C₆ alkyl ester),amino groups may be converted to amides (for example as a NHCOC₁-C₆alkyl amide) or carbamates (for example as an NHC(═O)OC₁-C₆ alkyl orNHC(═O)OCH₂Ph carbamate), hydroxyl groups may be converted to ethers(for example an OC₁-C₆ alkyl or a O(C₁-C₆ alkyl)phenyl ether) or esters(for example a OC(═O)C₁-C₆ alkyl ester) and thiol groups may beconverted to thioethers (for example a tert-butyl or benzyl thioether)or thioesters (for example a SC(═O)C₁-C₆ alkyl thioester).

Examples of side chains of non-natural alpha amino acids include thosereferred to below in the discussion of suitable R₂ groups for use incompounds of the present invention.

As used herein the term “salt” includes base addition, acid addition andquaternary salts. Compounds of the invention which are acidic can formsalts, including pharmaceutically acceptable salts, with bases such asalkali metal hydroxides, e.g. sodium and potassium hydroxides; alkalineearth metal hydroxides e.g. calcium, barium and magnesium hydroxides;with organic bases e.g. N-methyl-D-glucamine, cholinetris(hydroxymethyl)amino-methane, L-arginine, L-lysine, N-ethylpiperidine, dibenzylamine and the like. Those compounds (I) which arebasic can form salts, including pharmaceutically acceptable salts withinorganic acids, e.g. with hydrohalic acids such as hydrochloric orhydrobromic acids, sulphuric acid, nitric acid or phosphoric acid andthe like, and with organic acids e.g. with acetic, tartaric, succinic,fumaric, maleic, malic, salicylic, citric, methanesulphonic,p-toluenesulphonic, benzoic, benzenesunfonic, glutamic, lactic, andmandelic acids and the like.

Compounds of the invention which contain one or more actual or potentialchiral centres, because of the presence of asymmetric carbon atoms, canexist as a number of diastereoisomers with R or S stereochemistry ateach chiral centre. The invention includes all such diastereoisomers andmixtures thereof.

As stated above, the esters of the invention are primarily prodrugs ofthe corresponding carboxylic acids to which they are converted byintracellular carboxylesterases. However, for so long as they remainunhydrolised, the esters may have HDAC inhibitory activity in their ownright. The compounds of the invention include not only the ester, butalso the corresponding carboxylic acid hydrolysis products.

The Hydroxamate Group —C(═O)NHOH

In the compounds of the invention, the hydroxamate group functions as ametal binding group, interacting with the metal ion at the active siteof the HDAC enzyme, which lies at the base of a pocket in the foldedenzyme structure.

The Ring or Ring System A

Ring or ring system A is a mono- bi- or tri-cyclic carbocyclic orheterocyclic ring system, optionally substituted. In the compounds ofthe invention, when bound to the HDAC enzyme's active site, ring or ringsystem A lies within or at the entrance to the pocket containing themetal ion, with the -{Linker]- radical extending deeper into that pocketlinking A to the metal binding hydroxamic acid group. In the art, thering or ring system A is sometimes informally referred to as the “headgroup” of the inhibitor. Examples of ring systems A include thefollowing:

wherein R₁₀ is hydrogen or optionally substituted C₁-C₆ alkyl, the bondintersected by the wavy line connects to the Linker radical in thecompounds (1), and wherein the grouping R₁R₂CHNHYL₁X₁[CH₂]_(z) in thecompounds (1) is linked to any convenient ring atom of the ring systemshown.

The -[Linker]- Radical

-[Linker]- represents a divalent linker radical linking a ring atom in Awith the hydroxamic acid group CONHOH, the length of the linker radical,from the terminal atom linked to the ring atom of A to the terminal atomlinked to the hydroxamic acid group, being equivalent to that of anunbranched saturated hydrocarbon chain of from 3-10 carbon atoms. Anunbranched saturated hydrocarbon chain of 3 carbon atoms has a length ofabout 2.5 angstroms, and one of 10 carbon atoms has a length of about11.3 angstroms. The length of ang given -[Linker]- radical can bedetermined from data on atom radii and bond lengths in the literature,or can be determined using chemical structure modelling software such asDS ViewerPro (Accelrys, Inc). The defined length of the-[Linker]-radical reflects the fact that the head group A may lie at theentrance to, or within, the metal ion-containing pocket at the activesite of the enzyme, and is therefore loosely related to the depth ofthat pocket. In many cases, the length of the linker will be equivalentto that of an unbranched saturated hydrocarbon chain of from 4 to 9carbon atoms, for example 5, 6 or 7 carbon atoms. Specific general typesof -[Linker]- radical are those discussed below as “Type 1”, “Type 2”,and “Type 3” linkers.

Type 1 Linkers

In this type, -[Linker]- represents a divalent radical of formula—(CH₂)_(x)-Z-L²- wherein

-   -   x is 0 or 1;    -   Z is a bond, —NR₃—, —NR₃C(═O)—, —C(═O)NR₃—, —NR₄C(═O)—NR₃—,        —C(═S)—NR₃, —C(═N)—NR₃—NR₃S(═O)₂—, or —S(═O)₂NR₃— wherein R₃ is        hydrogen or C₁-C₆ alkyl; —C(═O); or —S(═O)₂—; and    -   L² represents an optionally substituted, straight or branched,        C₄-C₇ alkylene, C₄-C₆ alkenylene or C₄-C₆ alkynylene radicals        which may optionally contain or terminate in an ether (—O—),        thioether (—S—) or amino (—NR^(A)—) link wherein R^(A) is        hydrogen or optionally substituted C₁-C₃ alkyl.

In one sub-class of this type of linker, in any compatible combination,x is 0; Z is —NH—, —C(═O)—, —NHC(═O)— or —C(═O)NH— and L² is —(CH₂)₅—,—(CH₂)₆—, or —(CH₂)₇—.

Type 2 Linkers

In this type, -[Linker]- represents a divalent radical of formula—(CH₂)_(x)-L³-Ar¹-L⁴- wherein

-   -   x is 0 or 1;    -   L³ is Z or L² or Z-L² wherein Z is as defined in relation to        Type 1 linkers and L² is a bond or an optionally substituted        divalent C₁-C₃ alkylene radical;    -   Ar¹ is a divalent phenyl radical or a divalent mono-, or        bi-cyclic heteroaryl radical having 5 to 13 ring members, and    -   L⁴ is a bond or optionally substituted —CH₂— or —CH═CH—.

In one sub-class of this type of linker, in any compatible combination,x is 0 or 1; L³ is Z or Z-L², wherein Z is —NH—, —NHS(═O)₂—, —S(═O)₂NH—or —S(═O)₂—; L² is —CH₂-L⁴ is a bond or —CH₂—; and Ar¹ is divalentradical selected from the following:

wherein X is O, S or NH.

Of the above Ar¹ radicals, the benzo[b]thiophen-6-yl radical

is a particular example

In another sub-class of this type of linker, in any compatiblecombination, x is 0; L³ is L², wherein L² is an straight chain C₃-C₅alkylene radical which may optionally contain an ether (—O—), thioether(—S—) or amino (—NR^(A)—) link wherein R^(A) is hydrogen or optionallysubstituted C₁-C₃ alkyl, for example hydroxyethyl; and Ar¹ is divalentradical selected from those listed in the preceding paragraph.

In yet another subclass of this type, x is 0, L³ and L⁴ are bonds, andAr¹ is a divalent phenyl radical or a divalent bicyclic heteroarylradical having 9 to 13 ring members, for example selected from thefollowing:

wherein X is selected from O, S and NH and P, Q, and U are independentlyselected from N and CH; and the bond marked ** is linked to the CONHOHgroup; and the bond marked * is linked to the ring or ring system A.

Type 3 Linkers

In this type, -[Linker]- represents a divalent radical of formula—(CH₂)_(x)-L³-B—Ar¹-L⁴- wherein x, Ar¹, L³ and L⁴ are as discussed withreference to Type 2 linkers above; and B is a mono- or bi-cyclicheterocyclic ring system.

In one subclass of this type of linker B is one of the following:

wherein X is N and W is NH, O or S.

The Ester Group R₁

The ester group R₁ must be one which in the compound of the invention ishydrolysable by one or more intracellular carboxylesterase enzymes to acarboxylic acid group. Intracellular carboxylesterase enzymes capable ofhydrolysing the ester group of a compound of the invention to thecorresponding acid include the three known human enzyme isotypes hCE-1,hCE-2 and hCE-3. Although these are considered to be the main enzymes,other enzymes such as biphenylhydrolase (BPH) may also have a role inhydrolysing the ester. In general, if the carboxylesterase hydrolysesthe free amino acid ester to the parent acid it will, subject to theN-carbonyl dependence of hCE-2 and hCE-3 discussed below, also hydrolysethe ester motif when covalently conjugated to the HDAC inhibitor. Hence,the broken cell assay described herein provide a straightforward, quickand simple first screen for esters which have the required hydrolysisprofile. Ester motifs selected in that way may then be re-assayed in thesame carboxylesterase assay when conjugated to the modulator via thechosen conjugation chemistry, to confirm that it is still acarboxylesterase substrate in that background.

Subject to the requirement that they be hydroysable by intracellularcarboxylesterase enzymes, examples of particular ester groups R₁ includethose of formula —(C═O)OR₉ wherein R₉ is (i) R₇R₈CH— wherein R₇ isoptionally substituted (C₁-C₃)alkyl-(Z¹)_(a)—(C₁-C₃)alkyl- or(C₂-C₃)alkenyl-(Z¹)_(a)-(C₁-C₃)alkyl- wherein a is 0 or 1 and Z¹ is —O—,—S—, or —NH—, and R₈ is hydrogen or (C₁-C₃)alkyl- or R₇ and R₈ takentogether with the carbon to which they are attached form an optionallysubstituted C₃-C₇ cycloalkyl ring or an optionally substitutedheterocyclic ring of 5- or 6-ring atoms; or (ii) optionally substitutedphenyl or monocyclic heterocyclic having 5 or 6 ring atoms. Within theseclasses, R9 may be, for example, methyl, ethyl, n- or iso-propyl, n- orsec-butyl, cyclohexyl, allyl, phenyl, benzyl, 2-, 3- or 4-pyridylmethyl,N-methylpiperidin-4-yl, tetrahydrofuran-3-yl or methoxyethyl. Currentlypreferred is where R9 is cyclopentyl.

Macrophages are known to play a key role in inflammatory disordersthrough the release of cytokines in particular TNFα and IL-1 (van Roonet al Arthritis and Rheumatism , 2003, 1229-1238). In rheumatoidarthritis they are major contributors to the maintenance of jointinflammation and joint destruction. Macrophages are also involved intumour growth and development (Naldini and Carraro Curr Drug TargetsInflamm Allergy, 2005, 3-8). Hence agents that selectively targetmacrophage cell proliferation could be of value in the treatment ofcancer and autoimmune disease. Targeting specific cell types would beexpected to lead to reduced side-effects. The inventors have discovereda method of targeting HDAC inhibitors to macrophages which is based onthe observation that the way in which the esterase motif is linked tothe HDAC inhibitor determines whether it is hydrolysed, and hencewhether or not it accumulates in different cell types. Specifically ithas been found that macrophages contain the human carboxylesterase hCE-1whereas other cell types do not. In the general formula (I) when thenitrogen of the esterase motif R₁R₂ CHNH— is not directly linked to acarbonyl (—C(═O)—), ie when Y is not a —C(═O), —C(═O)O— or —C(═O)NR₃—radical, the ester will only be hydrolysed by hCE-1 and hence the HDACinhibitors will only accumulate in macrophages. Herein, unless“monocyte” or “monocytes” is specified, the term macrophage ormacrophages will be used to denote macrophages (including tumourassociated macrophages) and/or monocytes.

The Amino Acid Side Chain R

Subject to the requirement that the ester group R₁ be hydrolysable byintracellular carboxylesterase enzymes, the identity of the side chaingroup R₂ is not critical.

Examples of amino acid side chains includeC₁-C₆ alkyl, phenyl, 2-, 3-, or 4-hydroxyphenyl, 2-, 3-, or4-methoxyphenyl, 2,-3-, or 4-pyridylmethyl, benzyl, phenylethyl, 2-, 3-,or 4-hydroxybenzyl, 2,-3-, or 4-benzyloxybenzyl, 2,-3-, or 4-C₁-C₆alkoxybenzyl, and benzyloxy(C₁-C₆alkyl)-groups;the characterising group of a natural a amino acid, in which anyfunctional group may be protected;groups -[Alk]_(n)R₆ where Alk is a (C₁-C₆)alkyl or (C₂-C₆)alkenyl groupoptionally interrupted by one or more —O—, or —S— atoms or —N(R₇)—groups [where R₇ is a hydrogen atom or a (C₁-C₆)alkyl group], n is 0 or1, and R₆ is an optionally substituted cycloalkyl or cycloalkenyl group;a benzyl group substituted in the phenyl ring by a group of formula—OCH₂COR₈ where R₈ is hydroxyl, amino, (C₁-C₆)alkoxy,phenyl(C₁-C₆)alkoxy, (C₁-C₆)alkylamino, di((C₁-C₆)alkyl)amino,phenyl(C₁-C₆)alkylamino, the residue of an amino acid or acid halide,ester or amide derivative thereof, said residue being linked via anamide bond, said amino acid being selected from glycine, α or β alanine,valine, leucine, isoleucine, phenylalanine, tyrosine, tryptophan,serine, threonine, cysteine, methionine, asparagine, glutamine, lysine,histidine, arginine, glutamic acid, and aspartic acid;a heterocyclic(C₁-C₈)alkyl group, either being unsubstituted or mono- ordi-substituted in the heterocyclic ring with halo, nitro, carboxy,(C₁-C₆)alkoxy, cyano, (C₁-C₆)alkanoyl, trifluoromethyl(C₁-C₆)alkyl,hydroxy, formyl, amino, (C₁-C₆)alkylamino, di-(C₁-C₆r)alkylamino,mercapto, (C₁-C₆)alkylthio, hydroxy(C₁-C₆)alkyl, mercapto(C₁-C₆)alkyl or(C₁-C₆)alkylphenylmethyl; anda group —CR_(a)R_(b)R_(c) in which:

-   -   each of R_(a), R_(b) and R_(c) is independently hydrogen,        (C₁-C₆)alkyl, (C₂-C₆)alkenyl, (C₂-C₆)alkynyl,        phenyl(C₁-C₆)alkyl, (C₃-C₈)cycloalkyl; or    -   R_(c) is hydrogen and R_(a) and R_(b) are independently phenyl        or heteroaryl such as pyridyl; or    -   R_(c) is hydrogen, (C₁-C₆)alkyl, (C₂-C₆)alkenyl, (C₂-C₆)alkynyl,        phenyl(C₁-C₆)alkyl, or (C₃-C₈)cycloalkyl, and R_(a) and R_(b)        together with the carbon atom to which they are attached form a        3 to 8 membered cycloalkyl or a 5- to 6-membered heterocyclic        ring; or    -   R_(a), R_(b) and R_(c) together with the carbon atom to which        they are attached form a tricyclic ring (for example adamantyl);        or    -   R_(a) and R_(b) are each independently (C₁-C₆)alkyl,        (C₂-C₆)alkenyl, (C₂-C₆)alkynyl, phenyl(C₁-C₆)alkyl, or a group        as defined for R_(c) below other than hydrogen, or R_(a) and        R_(b) together with the carbon atom to which they are attached        form a cycloalkyl or heterocyclic ring, and R_(c) is hydrogen,        —OH, —SH, halogen, —CN, —CO₂H, (C₁-C₄)perfluoroalkyl, —CH₂OH,        —CO₂(C₁-C₆)alkyl, —O(C₁-C₆)alkyl, —O(C₂-C₆)alkenyl,        —S(C₁-C₆)alkyl, —SO(C₁-C₆)alkyl, —SO₂(C₁-C₆) alkyl,        —S(C₂-C₆)alkenyl, —SO(C₂-C₆)alkenyl, —SO₂(C₂-C₆)alkenyl or a        group -Q-W wherein Q represents a bond or —O—, —S—, —SO— or        —SO₂— and W represents a phenyl, phenylalkyl, (C₃-C₈)cycloalkyl,        (C₃-C₈)cycloalkylalkyl, (C₄-C₈)cycloalkenyl,        (C₄-C₈)cycloalkenylalkyl, heteroaryl or heteroarylalkyl group,        which group W may optionally be substituted by one or more        substituents independently selected from, hydroxyl, halogen,        —CN, —CO₂H, —CO₂(C₁-C₆)alkyl, —CONH₂, —CONH(C₁-C₆)alkyl,        —CONH(C₁-C₆alkyl)₂, —CHO, —CH₂OH, (C₁-C₄)perfluoroalkyl,        —O(C₁-C₆)alkyl, —S(C₁-C₆)alkyl, —SO(C₁-C₆)alkyl,        —SO₂(C₁-C₆)alkyl, —NO₂, —NH₂, —NH(C₁-C₆)alkyl,        —N((C₁-C₆)alkyl)₂, —NHCO(C₁-C₆)alkyl, (C₁-C₆)alkyl,        (C₂-C₆)alkenyl, (C₂-C₆)alkynyl, (C₃-C₈)cycloalkyl,        (C₄-C₈)cycloalkenyl, phenyl or benzyl.

Examples of particular R₂ groups include hydrogen (the glycine “sidechain”), benzyl, phenyl, cyclohexylmethyl, cyclohexyl,pyridin-3-ylmethyl, tert-butoxymethyl, iso-butyl, sec-butyl, tert-butyl,1-benzylthio-1-methylethyl, 1-methylthio-1-methylethyl, 1mercapto-1-methylethyl, and phenylethyl. Presently preferred R₂ groupsinclude phenyl, benzyl, and iso-butyl.

For compounds of the invention which are to be administeredsystemically, esters with a slow rate of carboxylesterase cleavage arepreferred, since they are less susceptible to pre-systemic metabolism.Their ability to reach their target tissue intact is thereforeincreased, and the ester can be converted inside the cells of the targettissue into the acid product. However, for local administration, wherethe ester is either directly applied to the target tissue or directedthere by, for example, inhalation, it will often be desirable that theester has a rapid rate of esterase cleavage, to minimise systemicexposure and consequent unwanted side effects. In the compounds of thisinvention, if the carbon adjacent to the alpha carbon of the alpha aminoacid ester ester is monosubstituted, i.e. R₂ is CH₂R^(z) (R^(z) beingthe mono-substituent) then the esters tend to be cleaved more rapidlythan if that carbon is di- or tri-substituted, as in the case where R₂is, for example, phenyl or cyclohexyl.

The Radical —Y-L¹-X¹—[CH₂]_(z)—

This radical (or bond) arises from the particular chemistry strategychosen to link the amino acid ester motif R₁CH(R₂)NH— to the head groupA of the inhibitor. Clearly the chemistry strategy for that coupling mayvary widely, and thus many combinations of the variables Y, L¹, X¹ and zare possible. However, as mentioned above, when the inhibitor is boundto the HDAC enzyme at its active site, the head group A is located atthe top of, or within, the metal-ion-containing pocket of the enzyme, soby linking the amino acid ester motif to the head group it generallyextends in a direction away from that pocket, and thus minimises oravoids interference with the binding mode of the inhibitor templateA-[Linker]-CONHOH. Hence the precise combination of variable making upthe linking chemistry between the amino acid ester motif and the headgroup A will often be irrelevant to the primary binding mode of thecompound as a whole. On the other hand, that linkage chemistry may insome cases pick up additional binding interactions with the enzyme atthe top of, or adjacent to, the metal ion-containing pocket, therebyenhancing binding.

It should also be noted that the benefits of the amino acid ester motifdescribed above (facile entry into the cell, carboxylesterase hydrolysiswithin the cell, and accumulation within the cell of active carboxylicacid hydrolysis product) are best achieved when the linkage between theamino acid ester motif and the head group is not a substrate forpeptidase activity within the cell, which might result in cleavage ofthe amino acid from the molecule. Of course, stability to intracellularpeptidases is easily tested by incubating the compound with disruptedcell contents, and analysing for any such cleavage.

With the foregoing general observations in mind, taking the variablesmaking up the radical —Y-L¹-X¹—[CH_(n)]_(z)— in turn:

-   -   z may be 0 or 1, so that a methylene radical linked to the head        group A is optional;    -   specific preferred examples of Y when macrophage selectivity is        not required include —(C═O)—, —(C═O)NH—, and —(C═O)O—; Where        macrophage selectivity is required any of the other options for        Y, including the case where Y is a bond, are appropriate.    -   In the radical L¹, examples of Alk¹ and Alk² radicals, when        present, include —CH₂—, —CH₂CH₂— —CH₂CH₂CH₂—, —CH₂CH₂CH₂CH₂—,        —CH═CH—, —CH═CHCH₂—, —CH₂CH═CH—, CH₂CH═CHCH₂—C≡C—, —C≡CH₂—,        CH₂C═C≡C—, and CH₂C≡CCH₂. Additional examples of Alk¹ and Alk²        include —CH₂W—, —CH₂CH₂W— —CH₂CH₂WCH₂—, —CH₂CH₂WCH(CH₃)—,        —CH₂WCH₂CH₂—, —CH₂WCH₂CH₂WCH₂—, and —WCH₂CH₂— where W is —O—,        —S—, —NH—, —N(CH₃)—, or —CH₂CH₂N(CH₂CH₂OH)CH₂—. Further examples        of Alk¹ and Alk² include divalent cyclopropyl, cyclopentyl and        cyclohexyl radicals.    -   In L¹, when n is 0, the radical is a hydrocarbon chain        (optionally substituted and perhaps having an ether, thioether        or amino linkage). Presently it is preferred that there be no        optional substituents in L¹. When both m and p are 0, L¹ is a        divalent mono- or bicyclic carbocyclic or heterocyclic radical        with 5-13 ring atoms (optionally substituted). When n is I and        at least one of m and p is 1, L¹ is a divalent radical including        a hydrocarbon chain or chains and a mono- or bicyclic        carbocyclic or heterocyclic radical with 5-13 ring atoms        (optionally substituted). When present, Q may be, for example, a        divalent phenyl, naphthyl, cyclopropyl, cyclopentyl, or        cyclohexyl radical, or a mono-, or bi-cyclic heterocyclicl        radical having 5 to 13 ring members, such as piperidinyl,        piperazinyl, indolyl, pyridyl, thienyl, or pyrrolyl radical, but        1,4-phenylene is presently preferred.    -   Specifically, in some embodiments of the invention, L¹, m and p        may be 0 with n being 1. In other embodiments, n and p may be 0        with m being 1. In further embodiments, m, n and p may be all 0.        In still further embodiments m may be 0, n may be 1 with Q being        a monocyclic heterocyclic radical, and p may be 0 or 1. Alk¹ and        Alk², when present, may be selected from —CH₂—, —CH₂CH₂—, and        —CH₂CH₂CH₂— and Q may be 1,4-phenylene.

Specific examples of the radical —Y-L¹-X¹—[CH₂]_(z)— include —C(═O)— and—C(═O)NH— as well as —(CH₂)_(v)—, —(CH₂)_(v)O—, —C(═O)—(CH₂)_(v)—,—C(═O)—(CH₂)_(v)O—, —C(═O)—NH—(CH₂)_(w)—, —C(═O)—NH—(CH₂)_(w)O—

wherein v is 1, 2, 3 or 4 and w is 1, 2 or 3, such as —CH₂—, —CH₂O—,—C(═O)—CH₂—, —C(═O)—CH₂O—, —C(═O)—NH—CH₂—, and —C(═O)—NH—CH₂O—.

Examples of particular subsets of compounds of the invention includethose of formulae (IA) to (IM):

wherein z, R₁, R₂, R₃, L¹ and X¹ and Y are as defined in relation toformula (I), and as discussed above, including the preferences therefor.

Examples of specific compounds of the invention include the following

-   (S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-acetic    acid cyclopentyl ester-   (S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-phenyl-butyric    acid cyclopentyl ester-   (S)-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-acetic    acid cyclopentyl ester-   (S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-methyl-pentanoic    acid cyclopentyl ester-   (S)-{2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenyl]-ethylamino}-phenyl-acetic    acid cyclopentyl ester-   (S)-2-{3-[3-(7-Hydroxycarbamoyl-heptanoyiamino)-phenoxy]-propylamino}-3-phenyl-propionic    acid cyclopentyl ester-   (S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-3-(4-hydroxy-phenyl)-propionic    acid cyclopentyl ester-   (S)-3-tert-Butoxy-2-(4-{[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-propionic    acid cyclopentyl ester-   (S)-1-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzyl)-pyrrolidine-2-carboxylic    acid cyclopentyl ester-   (S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-propionic    acid cyclopentyl ester-   (4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-acetic    acid cyclopentyl ester

Compounds of the invention may be prepared, for example, by the methodsdescribed below and in the Examples herein.

For example, compounds of the invention may be prepared from thecorresponding carboxylic acids (II)

by reaction of an activated derivative thereof, such as the acidchloride, with hydroxylamine or a protected version of hydroxylamine.

Alternatively, an N- or O-protected or N,O-diprotected precursor of thedesired compound (I) may be deprotected. In a useful version of thismethod O-protection is provided by a resin support, from which thedesired hydroxamic acid (I) may be cleaved, for example by acidhydrolysis.

Carboxyl protected derivatives of compounds (II), or O-linkedresin-supported derivatives of compounds (II) of the invention may besynthesised in stages by literature methods, selected according to theparticular structure of the desired compound. In that connection, thepatent publications listed above provide information on the synthesis ofHDAC inhibitors which are structurally similar to those of the presentinvention.

In one approach, suitable for compounds (I) wherein Z is a sulfonamidoradical —NHSO₂—, an amine (III)

may be reacted with an activated derivative, for example the acidchloride, of a sulfonic acid HOSO₂-L²-Z² wherein Z² is a protectedcarboxyl group, such as cleavable ester, or an O-linked resin-supportedhydroxamic acid group.

In another approach, suitable for compounds (I) wherein Z is an amideradical —NHC(═O)—, an amine (III) may be reacted with a carboxylic acidHOC(═O)-L-Z², Z² being as defined in the preceding paragraph, in thepresence of a carbodiimide coupling agent.

The case of compounds (i) where the ring or ring system A is linked tothe -Linker-CONHOH moiety via a ring nitrogen, and Z is —(C═O)— or—SO₂—, the appropriate N-heterocycle (IV)

may be reacted with the corresponding carboxylic or sulfonic acid (i.e.HOOC-L²-Z² or HOSO₂-L²-Z² wherein Z² is as defined above), either as anactivated derivative thereof such as the chloride, or in the presence ofa carbodiimide coupling agent.

By way of further illustration of the use of literature methods for thesynthesis of compounds within the scope of formula (I) above, thefollowing reaction schemes 1-6 are presented. In these schemes the groupR represents the radical

present in the compounds of the invention, or represents a functionalgroup upon which that radical may be built up using literature methods.

Also in the schemes, the symbol

represents a solid phase resin support.

As mentioned above, the compounds with which the invention is concernedare HDAC inhibitors, and may therefore be of use in the treatment ofcell proliferative disease, such as cancer, in humans and other mammals.

It will be understood that the specific dose level for any particularpatient will depend upon a variety of factors including the activity ofthe specific compound employed, the age, body weight, general health,sex, diet, time of administration, route of administration, rate ofexcretion, drug combination and the severity of the particular diseaseundergoing treatment. Optimum dose levels and frequency of dosing willbe determined by clinical trial.

The compounds with which the invention is concerned may be prepared foradministration by any route consistent with their pharmacokineticproperties. The orally administrable compositions may be in the form oftablets, capsules, powders, granules, lozenges, liquid or gelpreparations, such as oral, topical, or sterile parenteral solutions orsuspensions. Tablets and capsules for oral administration may be in unitdose presentation form, and may contain conventional excipients such asbinding agents, for example syrup, acacia, gelatin, sorbitol,tragacanth, or polyvinyl-pyrrolidone; fillers for example lactose,sugar, maize-starch, calcium phosphate, sorbitol or glycine; tablettinglubricant, for example magnesium stearate, talc, polyethylene glycol orsilica; disintegrants for example potato starch, or acceptable wettingagents such as sodium lauryl sulphate. The tablets may be coatedaccording to methods well known in normal pharmaceutical practice. Oralliquid preparations may be in the form of, for example, aqueous or oilysuspensions, solutions, emulsions, syrups or elixirs, or may bepresented as a dry product for reconstitution with water or othersuitable vehicle before use. Such liquid preparations may containconventional additives such as suspending agents, for example sorbitol,syrup, methyl cellulose, glucose syrup, gelatin hydrogenated ediblefats; emulsifying agents, for example lecithin, sorbitan monooleate, oracacia; non-aqueous vehicles (which may include edible oils), forexample almond oil, fractionated coconut oil, oily esters such asglycerine, propylene glycol, or ethyl alcohol; preservatives, forexample methyl or propyl p-hydroxybenzoate or sorbic acid, and ifdesired conventional flavouring or colouring agents.

For topical application to the skin, the drug may be made up into acream, lotion or ointment. Cream or ointment formulations which may beused for the drug are conventional formulations well known in the art,for example as described in standard textbooks of pharmaceutics such asthe British Pharmacopoeia.

For topical application by inhalation, the drug may be formulated foraerosol delivery for example, by pressure-driven jet atomizers orultrasonic atomizers, or preferably by propellant-driven meteredaerosols or propellant-free administration of micronized powders, forexample, inhalation capsules or other “dry powder” delivery systems.Excipients, such as, for example, propellants (e.g. Frigen in the caseof metered aerosols), surface-active substances, emulsifiers,stabilizers, preservatives, flavorings, and fillers (e.g. lactose in thecase of powder inhalers) may be present in such inhaled formulations.For the purposes of inhalation, a large number of apparata are availablewith which aerosols of optimum particle size can be generated andadministered, using an inhalation technique which is appropriate for thepatient. In addition to the use of adaptors (spacers, expanders) andpear-shaped containers (e.g. Nebulator®, Volumatic®), and automaticdevices emitting a puffer spray (Autohaler®), for metered aerosols, inparticular in the case of powder inhalers, a number of technicalsolutions are available (e.g. Diskhaler®, Rotadisk®, Turbohaler® or theinhalers for example as described in European Patent Application EP 0505 321).

For topical application to the eye, the drug may be made up into asolution or suspension in a suitable sterile aqueous or non aqueousvehicle. Additives, for instance buffers such as sodium metabisulphiteor disodium edeate; preservatives including bactericidal and fungicidalagents such as phenyl mercuric acetate or nitrate, benzalkonium chlorideor chlorhexidine, and thickening agents such as hypromellose may also beincluded.

The active ingredient may also be administered parenterally in a sterilemedium. Depending on the vehicle and concentration used, the drug caneither be suspended or dissolved in the vehicle. Advantageously,adjuvants such as a local anaesthetic, preservative and buffering agentscan be dissolved in the vehicle.

The following Examples illustrate the preparation of specific compoundsof the invention, and the HDAC inhibitory properties thereof: In theExamples:

Commercially available reagents and solvents (HPLC grade) were usedwithout further purification.

Microwave irradiation was carried out using a CEM Discover focusedmicrowave reactor.

Solvents were removed using a GeneVac Series I without heating or aGenevac

Series II with VacRamp at 30° C. or a Buchi rotary evaporator.

Purification of compounds by flash chromatography column was performedusing silica gel, particle size 40-63 μm (230-400 mesh) obtained fromSilicycle. Purification of compounds by preparative HPLC was performedon Gilson systems using reverse phase ThermoHypersil-Keystone HyperprepHS C18 columns (12 μm, 100×21.2 mm), gradient 20-100% B (A=water/0.1%TFA, B=acetonitrile/0.1% TFA) over 9.5 min, flow=30 ml/min, injectionsolvent 2:1 DMSO:acetonitrile (1.6 ml), UV detection at 215 nm.

¹H NMR spectra were recorded on a Bruker 400 MHz AV spectrometer indeuterated solvents. Chemical shifts (6) are in parts per million.Thin-layer chromatography (TLC) analysis was performed with Kieselgel 60F₂₅₄ (Merck) plates and visualized using UV light.

Analytical HPLCMS was performed on Agilent HPI 100, Waters 600 or Waters1525 LC systems using reverse phase Hypersil BDS C18 columns (5 μm,2.1×50 mm), gradient 0-95% B (A=water/0.1% TFA, B=acetonitrile/0.1% TFA)over 2.10 min, flow=1.0 ml/min. UV spectra were recorded at 215 nm usinga Gilson G1315A Diode Array Detector, G1214A single wavelength UVdetector, Waters 2487 dual wavelength UV detector, Waters 2488 dualwavelength UV detector, or Waters 2996 diode array UV detector. Massspectra were obtained over the range m/z 150 to 850 at a sampling rateof 2 scans per second or 1 scan per 1.2 seconds using Micromass LCT withZ-spray interface or Micromass LCT with Z-spray or MUX interface. Datawere integrated and reported using OpenLynx and OpenLynx Browsersoftware

The following abbreviations have been used:

MeOH=methanolEtOH=ethanolEtOAc=ethyl acetateBoc=tert-butoxycarbonylCbz=carbobenzyloxyDCM=dichloromethaneDCE=dichloroethaneDMF=dimethylformamideDMSO=dimethyl sulfoxideTFA=trifluoroacetic acidTHF=tetrahydrofuranNa₂CO₃=sodium carbonateHCl=hydrochloric acidDIPEA=diisopropylethylamineNaH=sodium hydrideNaOH=sodium hydroxideNaHCO₃=sodium hydrogen carbonatePd/C=palladium on carbonTBME=tert-butyl methyl ether

DMAP=4-Dimethylaminopyridine

N₂=nitrogenPyBop=benzotriazole-1-yl-oxy-tris-pyrrolidino-phosphoniumhexafluorophosphateNa₂SO₄=sodium sulphateEt₃N=triethylamineNH₃=ammoniaTMSCl=trimethylchlorosilaneNH₄Cl=ammonium chlorideLiAlH₄=lithium aluminium hydridepyBrOP=Bromo-tris-pyrrolidino phosphoniumhexafluorophosphateMgSO₄=magnesium sulfateMnO₂=Manganese dioxide^(n)BuLi=n-butyllithiumCO₂=carbon dioxideEDCI=N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochlorideEt₂O′=diethyl etherLiOH=lithium hydroxideHOBt=1-hydroxybenzotriazoleDIAD=Diisopropyl azodicarboxylateHATU=O-(7-Azabenzotriazol-1-yl-N,N,N′,N′-tetramethyluroniumhexafluorophosphate

ELS=Evaporative Light Scattering

TLC=thin layer chromatography

To a round bottomed flask charged with 2-chlorotrityl-O—NH₂ resin (6 g,loading 1.14 mmol/g, 6.84 mmol) and DCM (60 ml) was addeddiisopropylethylamine (5.30, 41.0 mmol, 6 eq). Methyl8-chloro-8-oxooctanoate (4.2 g, 20.5 mmol, 3 eq) was slowly added to thereaction mixture with orbital shaking and the reaction mixture shakenfor 48 hours. The resin was filtered and washed using the standardwashing procedure. The resin was dried under vacuum. LCMS purity wasdetermined by ELS detection, 100%, m/z 204 [M⁺+H]⁺.

Stage 2—Saponification

To a round bottomed flask charged with stage 1 resin (4 g, loading 1.14mmol/g, 4.56 mmol) was added THF (16 ml) and MeOH (16 ml). To thereaction was added a solution of NaOH (0.91 g, 22.8 mmol, 5 eq) in water(16 ml). The reaction mixture was shaken for 48 hours. The resin wasfiltered and washed with water×2, MeOH×2, followed by the standard washprocedure. The resin was dried under vacuum. LCMS purity was determinedby ELS detection, 100% m/z 190 [M⁺+H]⁺.

Preparation of Cyclopentyl Esters

The esters were prepared according to one of the following methods.Method A—Synthesis of (S)-2-Amino-3-tert-butoxy-propionic acidcyclopentyl ester

Stage 1: (S)-2-Benzyloxycarbonylamino-3-tert-butoxy-propionic acidcyclopentyl ester

ml=millilitreg=gram(s)mg=milligram(s)mol=molesmmol=millimole(s)eq=mole equivalentLCMS=high performance liquid chromatography/mass spectrometryNMR=nuclear magnetic resonancer.t.=room temperature

Standard Wash Procedure for Resin Chemistry

Resin was washed in the following sequence: DMF, MeOH, DMF, MeOH, DCM,MeOH, DCM, MeOH×2, TBME×2.

Resin Test Cleavage

A small amount of functionalised hydroxylamine 2-chlorotrityl resin (ca0.3 ml of reaction mixture, ca 10 mg resin) was treated with 2% TFA/DCM(0.5 ml) for 10 min at room temperature. The resin was filtered and thefiltrate was concentrated by blowing with a stream of N₂ gas. LCMS ofthe residue was obtained.

(Note: For functionalized hydroxylamine Wang resin test cleavage wascarried out using 50% TFA/DCM).Preparation of Suberic acid Derivatised Hydroxylamine 2-ChlorotritylResin

Stage 1—Immobilisation to 2-chlorotrityl-O—NH₂ Resin

(S)-2-Benzyloxycarbonylamino-3-tert-butoxy-propionic acid (4 g, 0.014mol) was dissolved in DMF (40 ml). Cyclopentanol (2.54 ml, 0.027 mol)and dimethylaminopyridine (0.165 g, 0.014 mol) were added. The solutionwas cooled to 0° C. using an ice bath and to it was addedN-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (2.73 g,0.014 mol, 1.05 eq.). The mixture was stirred at 0° C. for 10 minutesand then allowed to warm to r.t. and stirred for a further 18 hours. Tothe reaction mixture was added water (20-30 ml) followed by EtOAc (40ml). The layers were separated and the aqueous layer re-extracted withEtOAc (15 ml). The combined organic layers were washed with water (4×20ml), dried (MgSO₄) and the solvent removed in vacuo to give a residue.Purification by column chromatography (1:1 EtOAc/heptane) gave theproduct as a colourless oil (3.82 g, 78% yield). ¹H NMR (300 MHz,CDCl₃), δ: 1.15 (9H, s, CH₃×3), 1.50-1.90 (8H, m, CH₂×4), 3.57 (1H, dd,J=7.4, 1.2 Hz, CH), 3.85 (1H, dd, J=7.4, 1.2 Hz, CH), 4.45 (1H, m, CH),5.15 (2H, s, CH₂), 5.25 (1H, m, CH), 5.65 (1H, d, CH, J=7.6 Hz),7.30-7.50 (5H, m, ArH×5).

Stage 2: (S)-2-Amino-3-tert-butoxypropionic acid cyclopentyl ester

(S)-2-Benzyloxycarbonylamino-3-tert-butoxy-propionic acid cyclopentylester (3.82 g, 0.011 mol) was dissolved in EtOH (50 ml). 20% wt.Palladium hydroxide (wet) was added cautiously to the solution. Thesystem was evacuated and put under a hydrogen atmosphere for 4 hours.The system was evacuated and the palladium residues filtered off throughCelite. The Celite was thoroughly washed with EtOH (3×5 ml). The solventof the filtrate was removed in vacuo to give the product as a colourlessoil (2.41 g, 100% yield). ¹H NMR (300 MHz, CDCl₃), δ: 1.15 (9H, s,CH₃×3), 1.50-1.90 (10H, m, CH₂×4, NH₂), 3.50-3.70 (3H, m, CH₂, CH), 5.22(1H, s, CH).

Method B—Synthesis of (S)-Amino-cyclohexyl-acetic Acid Cyclopentyl Ester

Stage 1: (S)-tert-Butoxycarbonylamino-cyclohexyl-acetic Acid CyclopentylEster

This was prepared in the same manner as(S)-2-benzyloxycarbonylamino-3-tert-butoxy-propionic acid cyclopentylester (Method A, Stage 1) but from(S)-tert-butoxycarbonylamino-cyclohexyl acetic acid. ¹H NMR (300 MHz,CDCl₃), δ: 1.00-1.40 (10H, m, CH×10), 1.45 (9H, s, C(CH₃)₃), 1.60-2.00(8H, m, 4×CH₂), 4.15 (1H, m, CH), 5.05 (1H, d, NH, J=7.6 Hz), 5.25 (1H,m, CH).

Stage 2: (S)-Amino-cyclohexyl-acetic acid cyclopentyl ester

(S)-tert-butoxycarbonylamino-cyclohexyl-acetic acid cyclopentyl ester(1.17 g, 3.60 mmol) was dissolved in a TFA/DCM mixture (1:1, 10 ml) at0° C. The solution was stirred for 90 minutes, the solvent removed invacuo. The residue was azetroped with a DCM/heptane mixture (2×) to givea gum. The gum was redissolved in DCM (10 ml) and washed with saturatedaqueous NaHCO₃ solution (3×10 ml), dried (MgSO₄) and filtered. Thesolvent of the filtrate was removed in vacuo to give the product as anoil (0.780 g, 78% yield). ¹H NMR (300 MHz, CDCl₃), δ: 1.00-1.40 (10H, m,CH×10), 1.50-2.00 (8H, m, CH×8), 3.25 (1H, d, CH, J=7.2 Hz), 5.20 (1H,m, CH).

Method C—Synthesis of (S)-2-Amino-4-methyl-pentanoic acid cyclopentylester

Stage 1: (S)-2-Amino-4-methyl-pentanoic acid cyclopentyl estertoluene-4-sulfonic acid

To a suspension of (S)-leucine (15 g, 0.11 mol) in cyclohexane (400 ml)was added cyclopentanol (103.78 ml, 1.14 mmol) and p-toluene sulfonicacid (23.93 g, 0.13 mol). The suspension was heated at reflux to effectsolvation. After refluxing the solution for 16 hours it was cooled togive a white suspension. Heptane (500 ml) was added to the mixture andthe suspension was filtered to give the product as a white solid (35 g,85% yield). ¹H NMR (300 MHz, MeOD), δ: 1.01 (6H, t, CH₃×2, J=5.8 Hz),1.54-2.03 (11H, m, 11×CH), 2.39 (3H, s, CH₃), 3.96 (1H, t, CH, J=6.5Hz), 5.26-5.36 (1H, m, CH), 7.25 (2H, d, ArH x 2, J=7.9 Hz), 7.72 (2H,d, ArH×2, J=8.3 Hz).

Stage 2: Synthesis of (S)-2-Amino-4-methyl-pentanoic acid cyclopentylester

A solution of (S)-2-amino-4-methyl-pentanoic acid cyclopentyl estertoluene-4-sulfonic acid (2.57 g, 0.013 mol) in DCM (5 ml) was washedwith saturated aqueous NaHCO₃ solution (2×3 ml). The combined aqueouslayers were back extracted with DCM (3×4 ml). The combined organiclayers were dried (MgSO₄), and the solvent removed in vacuo to give acolourless oil (1.10 g, 80% yield). ¹H NMR (300 MHz, CDCl₃), δ: 0.90(6H, t, CH₃×2, J=6.4 Hz), 1.23-1.94 (11H, m, 5×CH₂, CH), 3.38 (1H, dd,CH, J=8.4, 5.9 Hz), 5.11-5.22 (1H, m, CH).

Method D—Synthesis of (S)-2-Amino-3-tert-butylsulfanyl-propionic acidcyclopentyl ester

Stage 1:(S)-3-tert-Butylsulfanyl-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionicacid cyclopentyl ester

This was prepared in the same manner as(S)-2-Benzyloxycarbonylamino-3-tert-butoxy-propionic acid cyclopentylester (Method A, Stage 1) but from(S)-3-tert-Butylsulfanyl-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionicacid. ¹H NMR (300 MHz, CDCl₃), δ: 1.30 (9H, s, (CH₃)₃), 1.55-1.95 (8H,m, CH₂×4), 3.05 (2H, d, CH₂, J=4.8 Hz), 4.20-4.30 (1H, m, CH), 4.40 (2H,d, CH₂, J=7.5 Hz), 4.65 (1H, m, CH), 5.25 (1H, m, CH), 5.70 (1H, d, NH,J=7.8 Hz), 7.30-7.50 (4H, m, ArH×4), 7.65 (2H, d, J=7.5 Hz, ArH×2), 7.80(2H, d, J=7.5 Hz, ArH×2).

Stage 2: (S)-2-Amino-3-tert-butylsulfanyl-propionic acid cyclopentylester

(S)-3-tert-Butylsulfanyl-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionicacid cyclopentyl ester (1.63 g, 3.50 mmol) was dissolved in a CH₃CN (25ml) at 0° C. Piperidine (21 ml) was added to the solution. Afterstirring for 30 minutes, the solvent was removed in vacuo to give aresidue. Purification by column chromatography (EtOAc eluent) gave theproduct as a colourless oil (628 mg, 73% yield). ¹H NMR (300 MHz,CDCl₃), δ: 1.30 (9H, s, (CH₃)₃), 1.55-1.95 (8H, m, CH₂×4), 2.75 (1H, dd,CH, J=7.2, 12.3 Hz), 2.95 (1H, dd, CH, J=4.8, 12.3 Hz), 5.25 (1H, m,CH).

The following N-Cbz protected amino acids were converted to thecyclopentyl esters according to Method A (above)

-   (S)-2-Benzyloxycarbonylamino-succinic acid 4-tert-butyl ester-   (S)-2-Benzyloxycarbonylamino-succinamic acid-   (S)-2-Benzyloxycarbonylamino-4-carbamoyl-butyric acid-   (S)-2-Benzyloxycarbonylamino-3-(4-tert-butoxy-phenyl)-propionic acid-   (S)-2-Benzyloxycarbonylamino-3-hydroxy-butyric acid-   (S)-2-Benzyloxycarbonylamino-3,3-dimethyl-butyric acid-   (S)-2-Benzyloxycarbonylamino-3-(1H-indol-2-yl)-propionic acid-   (S)-2-Benzyloxycarbonylamino-6-tert-butoxycarbonylamino-hexanoic    acid    The following N-Boc protected amino acids were converted to the    cyclopentyl esters according to Method B (above)-   tert-Butoxycarbonylamino-acetic acid-   (S)-2-tert-Butoxycarbonylamino-3-methyl-pentanoic acid-   (S)-Pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester-   (S)-2-tert-Butoxycarbonylamino-3-methyl-butyric acid-   (S)-2-tert-Butoxycarbonylamino-4-methylsulfanyl-butyric acid

The following free amino acids were converted to the cyclopentyl estersaccording to Method C (above)

-   (S)-Amino-phenyl-acetic acid-   (S)-2-Amino-3-phenyl-propionic acid-   (S)-2-Amino-propionic acid-   (S)-2-Amino-4-methyl-pentanoic acid    Preparation of 6-formyl-benzo[b]thiophene-2-carboxylic acid    (1-isobutoxy-ethoxy) amide

The Synthesis is outlined below in Scheme 7.

Additional literature references relating to this route can be foundwithin Tetrahedron Letters, 35, 2, 219-222 & WO 05/034880

Stage 1: 4-(2-dimethylamino-vinyl)-3-nitrobenzoic acid methyl ester

Methyl 4-methyl-3-nitrobenzoate (5 g, 25.6 mmol) was dissolved in DMF(25 mL, 5 vol) and to this was added N,N-dimethylformamidedimethylacetal (4.4 mL, 33.3 mmol). The mixture was allowed to stir at140° C. for 3 h. The resulting deep red solution was allowed to cool andconcentrated under vacuum. The residue was triturated with methanol andfiltered. The filtrate was washed with methanol and dried on the sinterto yield 4-(2-dimethylamino-vinyl)-3-nitrobenzoic acid methyl ester (5.2g, 80%). ¹H NMR (300 MHz, DMSO), δ: 2.98 (6H, s, 2×CH₃), 3.87 (3H, s,CH₃), 5.58 (1H, m, CH), 7.72-7.83 (3H, m, ArH), 8.32 (1H, m, CH).

Stage 2: 4-Formyl-3-nitrobenzoic acid methyl ester

To a solution of the enamine (5 g, 20.0 mmol) in THF (50 mL, 10 vol) andwater (50 mL, 10 vol) was added sodium periodate (12.8 g, 60.0 mmol) andthe mixture allowed to stir for 2 h. The mixture was filtered and theresulting solids washed with EtOAc (500 mL). The organic layer wasisolated, washed with NaHCO₃ (3×100 mL) and dried (MgSO₄). Concentrationunder vacuum afforded 4-formyl-3-nitrobenzoic acid methyl ester (3.9 g,93%). LCMS m/z 210 [M⁺+H]⁺, ¹H NMR (300 MHz, DMSO), δ: 3.96 (3H, s,OMe), 8.01 (1H, d, ArH), 8.39 (1H, d, ArH), 8.54 (1H, s, ArH), 10.31(1H, s, CHO).

Stage 3: Benzo[b]thiophene-2,6-dicarboxylic acid 2-ethyl ester 6-methylester

A mixture of 4-formyl-3-nitrobenzoic acid methyl ester (3.9 g, 18.7mmol), mercapto-acetic acid ethyl ester (2.2 mL, 20.4 mmol) and K₂CO₃(3.3 g, 24 mmol) in DMF (40 ml, 10 vol) was heated to 50° C. overnight.After cooling to r.t. the mixture was poured onto ice-cold water (250mL) and the resulting mixture stirred for 40 min. The solid formed wasisolated by filtration, washed with water (4×50 mL) and dried undervacuum to afford the title compound (3.9 g, 80%). LCMS m/z 265 [M⁺+H]⁺,¹H NMR (300 MHz, CDCl₃) δ: 1.40 (3H, t J=6.8 Hz, CH₃), 3.95 (3H, s,OMe), 4.40 (2H, q J 7.2 Hz, CH₂), 7.88 (1H, d J=8.0 Hz, ArH), 7.97-8.09(2H, m. ArH), 8.56 (1H, s, ArH).

Stage 4: Benzo[b]thiophene-2,6-dicarboxylic acid 2-ethyl ester

A mixture of benzo[b]thiophene-2,6-dicarboxylic acid 2-ethyl ester6-methyl ester (3.9 g, 14.77 mmol) and Lithium iodide (10 g, 74.6 mmol)in anhydrous pyridine (30 ml, 9 vol) was stirred at reflux for 16 h.After cooling to r.t., the mixture was added (either as a melt orchipped out) to ice-cold 2N HCl (200 mL). The solid formed was isolatedby filtration and washed with water (3×50 mL). The product was purifiedby recrystallisation from methanol to give the title compound (1.8 g,49%). LCMS m/z 251 [M⁺+H]⁺, ¹H NMR (300 MHz, DMSO), δ: 1.35 (3H, t J=6.9Hz, CH₃), 4.38 (2H, q J=7.1 Hz, CH₂), 7.99 (1H, d J=8.3 Hz, ArH), 8.12(1H, d J=8.3 Hz, ArH), 8.27 (1H, s, ArH), 8.70 (1H, s, ArH).

Stage 5: 6-Hydroxymethyl-benzo[b]thiophene-2-carboxylic acid ethyl ester

A solution of benzo[b]thiophene-2,6-dicarboxylic acid 2-ethyl ester (1.6g, 6.4 mmol) in anhydrous THF (40 mL, 25 vol) was cooled to 0° C. Tothis BH₃ (1M in THF, 30 mL, 30.0 mmol) was added slowly. The reactionwas allowed to warm to r.t. and stirred for 3 h. The solution was thencooled to 0° C. and quenched using 1 N HCl (7.5 mL). The reactionmixture was concentrated under vacuum to remove all THF and theresulting solid isolated by filtration and dried under vacuum to give6-hydroxymethyl-benzo[b]thiophene-2-carboxylic acid ethyl ester (1.3 g,87%). LCMS m/z 237 [M⁺+H]⁺, ¹H NMR (300 MHz, DMSO), δ: 1.34 (3H, t J=6.9Hz, CH₃), 4.35 (2H, q J=7.1 Hz, CH₂), 4.65 (2H, s, CH₂), 6.53 (1H, br s,OH), 7.42 (1H, d J=9.4 Hz), 7.98 (3H, m, ArH), 8.18 (1H, s, ArH).

Stage 6: 6-Hydroxymethyl-benzo[b]thiophene-2-carboxylic acid

6-Hydroxymethyl-benzo[b]thiophene-2-carboxylic acid ethyl ester (2.4 g,9.6 mmol, 1 eq) was dissolved in THF (10 mL, 4 vol) and water added (10mL) along with LiOH (0.69 g, 28.8 mmol). The reaction mixture wasstirred at 50° C. for 3 h and then concentrated to dryness and takenonto the next step without purification.

Stage 7: 6-hydroxymethyl-benzo[b]thiophene-2-carboxylic acid(1-isobutoxy-ethoxy) amide

To a solution of 6-hydroxymethyl-benzo[b]thiophene-2-carboxylic acid(1.76 g, 8.4 mmol, 1 eq) in DMF was added PyBrOP (4.3 g, 9.2 mmol),O-(isobutoxy-ethyl)-hydroxylamine (11.5 mL, 84.0 mmol) (prepared viaprocedure in WO0160785) and DIPEA (2.9 mL, 16.7 mmol). The reactionmixture was allowed to stir at r.t. for 2 h then diluted with water (40mL) and EtOAc (40 mL). The organic layer was isolated, washed with brine(50 mL) and concentrated. The residue was purified by chromatography onsilica gel eluting with EtOAc/heptane (1:1) to afford the title compound(1.8 g, 67% over 2 steps). LCMS m/z 322 [M⁺−H]⁺, ¹H NMR (300 MHz, MeOD),δ: 0.83 (6H, d J=6.6 Hz, 2×CH₃), 1.32 (3H, d J=5.9 Hz, CH₃), 1.75 (1H,m, CH), 3.38 (2H, m, CH₂), 4.63 (2H, s, CH₂), 4.95 (1H, m, CH), 7.32(1H, d J=8.2 Hz, ArH), 7.77 (3H, m, ArH).

Stage 8: 6-formyl-benzo[b]thiophene-2-carboxylic acid(1-isobutoxy-ethoxy) amide

To a solution of 6-hydroxymethyl-benzo[b]thiophene-2-carboxylic acid(1-isobutoxy-ethoxy) amide (600 mg, 1.86 mmol) in DCM (3 mL) was addedMnO₂ (2.1 g, 24.1 mmol). The mixture was stirred at ambient temperaturefor 30 min and then filtered through celite. The filtrate wasconcentrated to afford the title compound (435 mg, 82%). LCMS m/z 320[M⁺−H]⁺, ¹H NMR (300 MHz, MeOD), δ: 0.94 (6H, d J=6.7 Hz, 2×CH₃), 1.45(3H, d J=5.3 Hz, CH₃), 1.87 (1H, m, CH), 3.40 (2H, m, CH₂), 5.08 (1H, ddJ=5.2, 10.6 Hz, CH), 7.89-8.09 (3H, m, ArH), 8.55 (1H, s, ArH), 10.11(1H, s, CHO).

Synthesis of Compounds in FIG. 1 as Exemplified by Compound (1) andCompound (2)

Preparation of Building Blocks A-G Building Blocks A and B

N-Boc-D-tetrahydro-beta-carboline-3-carboxylic acid (5.0 g, 15.8 mmol)and TMSCl (20 ml, 158 mmol) in MeOH (50 ml) were heated under reflux for2 h. The reaction mixture was evaporated to dryness to yield(R)-2,3,4,9-Tetrahydro-1H-beta-carboline-3-carboxylic acid methyl ester(building block A). LCMS purity 100%. m/z 231 [M⁺+H]⁺, 461 [2M⁺+H]⁺.Building block A was used without further purification.

(S)-2,3,4,9-Tetrahydro-1H-beta-carboline-3-carboxylic acid methyl ester(building block B) was obtained by the same procedure as block A usingN-boc-L-tetrahydro-beta-carboline-3-carboxylic acid.

Building Block C

Stage 1: A solution of glyoxylic acid monohydrate (1.51 g, 16.4 mmol) inwater (10 ml) was added dropwise to a stirred solution of tryptamine.HCl(3.0 g, 15.3 mmol) in water (200 ml). KOH (0.827 g, 14.7 mmol) in water(10 ml) was added. The reaction mixture was stirred at room temperaturefor 1 h after which time precipitation occurred. Following filtrationunder reduced pressure the tetrahydro-beta-carboline-1-carboxylic acidwas collected and washed with water. Yield 1.9 g (58%); m/z 217 [M⁺+H]⁺.

Stage 2: A solution of tetrahydro-beta-carboline-1-carboxylic acid (7.4g) in MeOH (250 ml) was saturated with HCl gas for 20 min. The reactionmixture was gently stirred at room temperature for 18 h. and ca. 80%conversion was observed. The reaction mixture was re-treated with HClgas and allowed to stir for another 18 h. Upon completion of thereaction the mixture was concentrated in vacuo to yield2,3,4,9-tetrahydro-1H-beta-carboline-1-carboxylic acid methyl ester(building block C), LCMS purity 95%, m/z 231 [M⁺+H]⁺. The product wasused without further purification.

Building Block D

6-Methoxy-2,3,4,9-tetrahydro-1H-beta-carboline-1-carboxylic acid methylester

(building block D) was obtained from esterification of6-methoxy-tetrahydro-beta-carboline-1-carboxylic acid using theprocedure as for building block C. Building block D: LCMS purity 98%,m/z 261 [M⁺+H]⁺. Building block D was used without further purification.

Building Block E

A solution 4-piperazin-1-yl-benzonitrile (1.5 g, 8.0 mmol) in MeOH (150ml) was saturated with HCl gas. Water (0.17 ml) was added and themixture was heated under reflux for 18 h. The reaction mixture wascooled to r.t. and was resaturated with HCl gas. This was refluxed for afurther 24 h. The mixture was concentrated under reduced pressureyielding 4-piperazin-1-yl-benzoic acid methyl ester (building block E).LCMS purity 90%, m/z 221 [M⁺+H]⁺. Building block E was used withoutfurther purification.

Building Block F

1,2,3,4-Tetrahydro-isoquinoline-7-carboxylic acid methyl ester (buildingblock F) was prepared following the same procedure as for building blockE. LCMS purity 89%. m/z 193 [M⁺+H]⁺. This product was used withoutfurther purification.

Building Block G

4-Amino-benzoic acid methyl ester (building block G) was commerciallyavailable

Synthesis of Compounds (1) and Compound (2)

Stage 1: Coupling with Building Block

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (4.6 g,loading 1.14 mmol, 5.24 mmol) was swollen in anhydrous DCM (50 ml).Building block A (4.76 g, 15.72 mmol) was added, followed by pyBOP (8.18g, 15.72 mmol, 3 eq) and DIPEA (6.77 g, 52.4 mmol, 10 eq). The reactionwas shaken for 18 h, filtered and washed using the standard washprocedure. The resin was dried under vacuum.

Note: For building block G, coupling using the above condition gave ca.10% conversion. Thus an alternative condition was used: Stage 2 resin(1.0 g, loading 1.14 mmol) was swollen in anhydrous DCM (100 ml).1-Chloro-N,N-2-trimethylpropenylamine (Ghosez reagent)¹ (7.53 ml, 57.0mmol, 50 eq) was added at 0° C. under the atmosphere of N₂. The mixturewas allowed to warm to room temperature and gently shaken for 1-2 h. Theaniline building block G (8.6 g, 57.0 mmol, 50 eq) was added portionwiseover 20 min. Et₃N (8.0 ml, 57.0 mmol, 50 eq) was added. The mixture wasshaken for 18 h. LCMS after a test cleave shows 70% conversion, m/z 323[M⁺+H]⁺, 645 [2M⁺+H]⁺. The resin was filtered and washed using thestandard wash procedure. The resin was dried under vacuum.

Stage 2: Saponification

Stage 1 resin (4.8 g, loading 1.14 mmol, 5.47 mmol) was suspended inMeOH (17.5 ml) and THF (17.5 ml). A solution of NaOH (1.1 g, 27.5 mmol,5 eq) in water (17.5 ml) was added. The mixture was shaken for 18 h.LCMS of the test cleave confirmed the completion of reaction, m/z 388[M⁺+H]⁺, 775 [2M⁺+H]⁺. The resin was filtered and washed with water×2,MeOH×2, followed by the standard wash procedure. The resin was driedunder vacuum.

Note: For building block E, saponification was carried out using 10 eq.of 2.7M NaOH and was shaken for 72 h.

Stage 3: Coupling with L-phenylglycine Cyclopentyl Ester

Stage 2 resin (2.4 g, loading 1.14 mmol, 2.7 mmol) was suspended inanhydrous DCM (30 ml). L-phenylglycine cyclopentylester tosyl salt (3.2g, 8.1 mmol, 3 eq) was added, followed by pyBOP (4.2 g, 8.1 mmol, 3 eq)and DIPEA (3.5 g, 27.0 mmol, 10 eq). The mixture was shaken for 18 h.The LCMS of the test cleave (i.e. a small quantity of resin was washedusing the standard wash procedure, dried, and cleaved in 2% TFANDCM.Resin was filtered off and filtrate concentrated to dryness. LCMS wasobtained) confirmed the completion of reaction, m/z 589 [M⁺+H]⁺. Thewhole sample of resin was filtered and washed using the standard washprocedure. The resin was dried under vacuum.

Note.

For compounds 5-8, L-phenylalanine ethyl ester (3 eq) was used.

For compound 19, L-phenylglycine t-butyl ester (3 eq) was used.

Stage 4:(S)-{[(R)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (1)

Stage 3 resin (1.0 g, loading 1.14 mmol) was gently shaken in 2% TFA/DCM(10 ml) for 20 mins. The resin was filtered. The filtrate was collectedand evaporated under reduced pressure at room temperature. The resin wasre-treated with 2% TFA/DCM (10 ml) and after 20 mins. The combinedfiltrates were evaporated to dryness under reduced pressure at r.t, theresidue (ca. 300 mg) was purified by preparative HPLC to yield compound(1), m/z 589 [M⁺+H]⁺; ¹H NMR (400 MHz, CD₃OD) δ: 1.3-1.7 (16H, m, CH₂),2.1-2.3 (2H, m, CH₂), 2.5 (2H, m, CH₂), 3.0-3.5 (2H, m, CH₂), 4.5-4.8(2H, m, CH₂), 5.1 (1H, m, CO₂CH), 5.2 (1H, dd, CH₂CHNCO), 5.5-5.9 (1H,d, CONHCHPh), 7.0-7.5 (9H, m, Ar).

The corresponding carboxylic acid was obtained by the followingprocedure

Stage 5: Saponification

Stage 3 resin (1.0 g, loading 1.14 mmol) was suspended in MeOH (4 ml)and THF (4 ml). A solution of NaOH (0.23 g, 5.7 mmol) in water (4 ml)was added. The mixture was shaken for 18 h. LCMS of the test cleaveconfirmed the completion of reaction, m/z 521 [M⁺+H]⁺. Resin wasfiltered and washed with water×2, MeOH×2, followed by the standard washprocedure. Resin was dried under vacuum.

Stage 6:(S)-{[(R)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-phenyl-aceticacid (2)

Stage 5 resin (1.0 g, loading 1.14 mmol) was cleaved using the procedureoutlined for Stage 6 yielding compound (2), m/z 521 [M⁺+H]⁺; ¹H NMR (400MHz, CD₃OD), δ: 1.3-1.5 (4H, 2×CH₂), 1.6-1.8 (4H, 2×CH₂), 2.1-2.2 (2H,m, CH₂), 2.4-2.7 (2H, m, CH₂), 3.0-3.2 (1H, m), 3.5 (1H, m), 4.55 (m),4.9 (m), 5.1-5.35 (2H, m), (2H, m, CH₂NCO), 5.75-5.8 (1H, 2×d, NHCHPh),7.0-7.5 (9H, m, Ar), 7.6 (d), 7.7 (d), 8.35 (d), 8.95 (s), 9.05 (s).

The following compounds were prepared according to the proceduredescribed for Compound (1) and Compound (2)

(S)-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (3)

Building block B Used

LCMS purity 98%, m/z 589 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20-1.40(8H, m, 4×CH₂), 1.40-1.80 (8H, m, 4×CH₂), 2.10 (2H, m, CH₂), 3.45 (2H,m, CH₂), 5.0 (2 H, m, CH₂ overlaps with D₂O peak), 5.25-5.45 (2H, m,2×CH), 5.50 (1H, s, CONHCHPh), 7.00-7.50 (9H, m, Ar).

(S)-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-phenyl-aceticacid (4) Building Block B Used

LCMS purity 100%, m/z 521 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ1.30-1.50(4H, m, 2×CH₂), 1.55-1.80 (4H, m, 2×CH₂), 2.15 (2H, m, CH₂), 2.60 (2H,m, CH₂), 3.00-3.25 (2H, m, CH₂), 3.40-3.55 (2H, m, CH₂), 5.20-5.30 (1H,m, CHCON), 5.35 (1H, s, NHCHPh), 7.05-7.50 (9H, m, Ar).

(S)-2-{[(R)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-3-phenyl-propionicacid ethyl ester (5) Building Block A Used

LCMS purity 100% m/z 563 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ1.00 (3H, t,CH₃), 1.20-1.24 (4H, m, 2×CH₂), 1.50-1.70 (4H, m, 2×CH₂), 2.00 (2H, m,CH₂), 2.30-2.50 (2H, m, CH₂), 2.80-3.00 (2H, m, CH₂), 4.05 (2H, q,CO₂CH₂), 4.35-4.50 (1H, m, CH), 4.80-5.05 (2H, m, CH₂), 5.40 (1H, s,NHPhCO), 6.80-7.30 (9H, m, Ar).

(S)-2-{[(R)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-3-phenyl-propionicacid (6) Building Block A Used

LCMS purity 100%, m/z 534 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ 1.30-1.50(4H, m, 2×CH₂), 1.60-1.80 (4H, m, 2×CH₂), 2.15 (2H, m, CH₂), 2.50 (2H,m, CH₂), 3.00 (2 H, m, CH₂), 3.20 (2H, m, CH₂), 4.30-4.80 (2H, m, CH₂),5.15 (1H, m, CH), 6.90-7.50 (9H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-3-phenyl-propionicacid ethyl ester (7) Building Block B Used

LCMS purity 100%, m/z 563 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ1.00 (3H, t,CH₃), 1.30-1.50 (4H, m, 2×CH₂), 1.60-1.70 (4H, m, 2×CH₂), 2.10 (2H, m,CH₂), 2.30-2.65 (2H, m, CH₂), 2.95-3.20 (2H, m, CH₂), 3.45 (1H, m, CH),4.05 (2H, q, CO₂CH₂), 4.35-4.50 (1H, m, CH), 4.80-5.05 (2H, m, CH₂),5.50 (1H, s, NHPhCO), 6.90-7.50 (9 H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-3-phenyl-propionicacid (8) Building Block B Used

LCMS purity 100%, m/z 534 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ 1.30-1.50(4H, m, 2×CH₂), 1.60-1.80 (4H, m, 2×CH₂), 2.15 (2H, m, CH₂), 2.50 (2H,m, CH₂), 2.95-3.15 (2H, m, CH₂), 3.20-3.50 (2H, m, CH₂), 4.30-4.50 (2H,m, 2×CH), 4.80-5.20 (2 H, m, CH₂), 6.90-7.50 (9H, m, Ar).

(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (9) Building Block C Used

LCMS purity 100%, m/z 589 [M⁺+H]⁺, ¹H NMR (400 MHz, CDCO₃), δ 1.30-1.80(16H, m, 8×CH₂), 2.15 (2H, m, CH₂), 2.45-2.70 (2H, m, CH₂), 2.95 (2H, m,CH₂), 3.55 (1 H, m, CH), 4.35 (1H, m, CH), 5.15 (1H, m, CO₂CH), 5.45(1H, m, CH), 6.20 (1H, d, PhCHNH) 7.00-7.80 (9H, m, Ar), 8.80-9.20 (1H,broad m, CHNHOH).

(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-phenyl-aceticacid (10) Building Block C Used

LCMS purity 100%, m/z 521 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ 1.30-1.50(4H, m, 2×CH₂), 1.60-1.80 (4H, m, 2×CH₂), 2.15 (2H, m, CH₂), 2.50-2.65(2H, m, CH₂), 2.95 (2H, m, CH₂), 3.70 (1H, dd, CH), 4.30 (1H, dd, CH),5.50 (1H, m, CH), 6.10 and 6.20 (0.5H each, s, PhCHNH) 7.00-7.50 (9H, m,Ar).

(S)-{([2-(7-Hydroxycarbamoyl-heptanoyl)-6-methoxy-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (11) Building Block D Used

LCMS purity 100%, m/z 619 [M⁺+H]⁺, ¹H NMR (400 MHz, CDCl₃), δ 1.30-1.80(16H, m, 8×CH₂), 2.15 (2H, m, CH₂), 2.50-2.65 (2H, m, CH₂), 2.85 (2H, m,CH₂), 3.70 (1 H, dd, CH), 3.80 (3H, s, OMe), 4.30 (1H, dd, CH), 5.20(1H, m, CO₂CH), 5.30-5.50 (1H, m, CH), 6.15-6.20 (1H, d, PhCHNH)6.80-7.80 (8H, m, Ar), 8.80-9.00 (1H, m, CONHOH).

(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-6-methoxy-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-phenyl-aceticacid (12) Building Block D Used

LCMS purity 100%, m/z 551 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ 1.30-1.60(8H, m, 4×CH₂), 2.05 (2H, m, CH₂), 2.50-2.65 (2H, m, CH₂), 2.80 (2H, m,CH₂), 3.55 (1H, dd, CH), 3.70 (3H, s, OMe), 4.30 (1H, dd, CH), 5.30-5.50(1H, m, CH), 5.90-6.10 (0.5H each, s, PhCHNH), 6.65 (1H, m, Ar), 6.80(1H, m, Ar), 7.10 (1H, m, Ar), 7.35 (5H, m, Ar).

(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-6-methoxy-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (13) Building Block E Used

LCMS purity 95%, m/z 579 [M⁺+H]⁺, ¹H NMR (400 MHz, CDCl₃), δ1.40-1.90(16H, m, 8×CH₂), 2.15 (2H, m, CH₂), 2.45 (2H, m, CH₂), 3.40 (4H, m,2×CH₂N), 3.60-3.80 (4H, m, 2×CH₂N), 5.30 (1H, m, CO₂CH), 5.70 (1H, d,PhCHNH), 6.90 (2H, d, Ar), 7.30-7.50 (6H, m, Ar), 7.80 (2H, d, Ar).

(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-6-methoxy-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-phenyl-aceticacid (14) Building Block E Used

LCMS purity 100%, m/z 511 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ1.30 (4H, m,2×CH₂), 1.50 (4H, m, 2×CH₂), 2.00 (2H, t, CH₂), 2.35 (2H, t, CH₂), 3.30(4H, m, 2×CH₂N), 3.70 (4H, m, 2×CH₂N), 5.55 (1H, s, PhCHNH), 6.90 (2H,d, Ar), 7.30 (3H, m, Ar), 7.40 (2H, m, Ar), 7.70 (2H, d, Ar).

(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-7-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (15) Building Block F Used

LCMS purity 100%, m/z 550 [M⁺+H]⁺, ¹H NMR (400 MHz, CDCl₃), δ 1.30-1.80(16H, m, 8×CH₂), 2.15 (2H, m, CH₂), 2.45 (2H, m, CH₂), 2.95 (2H, m,2×CH₂), 3.70-3.90 (2H, m, 2×CH₂), 4.60-4.70 (2H, m, CH₂), 5.25 (1H, m,CO₂CH), 5.70 (1H, m, PhCHNH), 7.20-7.70 (8H, m, Ar).

(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-7-carbonyl]-amino}-phenyl-aceticacid (16) Building Block F Used

LCMS purity 87%, m/z 482 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ 1.30-1.50(4H, m, 2×CH₂), 1.60-1.70 (4H, m, 2×CH₂), 2.15 (2H, m, CH₂), 2.50 (2H,m, CH₂), 2.95 (2 H, m, 2×CH₂), 3.70 (2H, m, CH₂), 4.80 (2H, m, CH₂),5.70 (1H, s, PhCHNH), 7.20-7.80 (8H, m, Ar).

(S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-phenyl-aceticacid cyclopentyl ester(17) Building Block G Used

LCMS purity 94%, m/z 510 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ1.30-1.80(16H, m, 8×CH₂), 2.00-2.20 (4H, m, 2×CH₂), 5.10-5.30 (1H, m, CO₂CH),5.70 (1H, m, PhCHNH), 7.30-7.80 (9H, m, Ar).

(S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-phenyl-aceticacid (18)

Building Block G Used

LCMS purity 100%, m/z 442 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ1.30-1.40(4H, m, 2×CH₂), 1.50-1.70 (4H, m, 2×CH₂), 2.20 (2H, t, CH₂), 2.35 (2H,t, CH₂), 5.70 (1H, s, PhCHNH), 7.25-7.40 (3H, m, Ar), 7.50 (2H, d, Ar),7.65 (2H, d, Ar), 7.80 (2H, d, Ar).

(S)-{[(R)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-3-carbonyl]-amino}-phenyl-aceticacid tert-butyl ester (19) Building Block A Used

LCMS purity 100%, m/z 577 [M⁺+H]⁺, ¹H NMR (400 MHz, CDCl₃), δ 1.20-1.40(17H, m, 4×CH₂ and C(CH₃)₃), 2.10 (2H, m, CH₂), 2.45 (2H, m, CH₂),3.15-3.60 (2H, m, CH₂), 4.75 (2H, m, CH₂), 5.35 (2H, m, PhCHNH and CH),6.90-7.50 (9H, m, Ar).

Synthesis of Compound (20) and Compound (21)

Stage 1: (S)-(4-Nitro-benzylamino)-phenyl-acetic acid cyclopentyl ester

A mixture of 4-nitrobenzyl bromide (15 g, 69.4 mmol), L-phenylglycinecyclopentylester tosyl salt (27.1 g, 60.4 mmol) and potassium carbonate(19.6 g, 138.8 mmol) in DMF (250 ml) was stirred at room temperature for18 h. The reaction mixture was diluted with EtOAc (300 ml) and washedwith water (3×200 ml). The EtOAc layer was isolated, dried (Na₂SO₄),filtered and concentrated to dryness yielding an orange colour oil. Acrude weight of 21 g was isolated. LCMS purity 81%, m/z 355 [M⁺+H]⁺.This product was used without further purification.

Stage 2: (S)-[tert-Butoxycarbonyl-(4-nitro-benzyl)-amino]-phenyl-aceticacid cyclopentyl ester

To a solution of Stage 1 product (15 g, 42.37 mmol) in THF (150 ml) wasadded K₂CO₃ (6.9 g, 50.8 mmol), followed by di-t-butyldicarbonate (22.2g, 101.7 mmol). Water (150 ml) was added and the reaction stirred atroom temperature for 36 h. The reaction mixture was evaporated todryness. The residue was redissolved in EtOAc (300 ml), washedconsecutively with 0.1 M HCl (150 ml), sat. aq. NaHCO₃ and water (150ml). The EtOAc layer was dried (Na₂SO₄), filtered and concentrated todryness yielding a yellow oil. After purification by columnchromatography (10% EtOAc/hexane) the product was obtained as clearyellow oil (12 g, 62% yield). LCMS purity 95%, m/z 455 [M⁺+H]⁺, 496[M⁺+H+41]⁺.

Stage 3: (S)-[(4-Amino-benzyl)-tert-butoxycarbonyl-amino]-phenyl-aceticacid cylopentyl ester

A mixture of Stage 2 product (12 g, 26.4 mmol) and 10% Pd/C (2.0 g) inEtOAc (350 ml) was hydrogenated at room temperature for 18 h. The Pd/Ccatalyst was filtered off through a pad of celite. The filtrate wasconcentrated under reduced pressure to yield a white solid (10.1 g, 90%yield). LCMS purity 100%, m/z 425 [M⁺+H]⁺, 466 [M⁺+H+41]⁺.

Stage 4: Coupling of stage 3 aniline

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (1.0 g,loading 0.94 mmol) was swollen in anhydrous DCM (100 ml).1-Chloro-N,N-2-trimethylpropenylamine (Ghosez reagent)¹ (0.373 ml, 2.82mmol, 3 eq) was added at 0° C. under the atmosphere of N₂. The mixturewas allowed to warm to room temperature and gently shaken for 1-2 h.Stage 3 aniline (1.2 g, 2.82 mmol, 3 eq) was added portionwise over 20min. Et₃N (0.53 ml, 3.76 mmol, 4 eq) was added. The mixture was shakenfor 1 h. LCMS after a test cleave shows 70% conversion, m/z 596 [M⁺+H]⁺.The resin was filtered and washed using the standard wash procedure. Theresin was dried under vacuum.

Stage 5:(S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid cyclopentyl ester (20)

Stage 4 resin (1.5 g, loading 0.94 mmol) was gently shaken in 2% TFA/DCM(10 ml) for 20 mins. The resin was filtered. The filtrate was collectedand evaporated under reduced pressure at room temperature. The resin wasre-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered. Thecombined filtrates were evaporated to dryness under reduced pressure atr. t to give a residue. This residue was allowed to stand in 20% TFA/DCMfor 40 mins. After evaporation to dryness, also under reduced pressureat r.t, the residue was purified by preparative HPLC to yield compound(20) as the TFA salt, LCMS purity 95%, m/z 496 [M⁺+H]⁺, ¹H NMR (400 MHz,DMSO), δ: 1.30-1.50 (6H, m, 3×CH₂), 1.50-1.70 (8H, m, 4×CH₂), 1.80 (2H,m, CH₂), 2.10 (2H, t, CH₂), 2.45 (2H, t, CH₂), 4.1 (2H, dd, CH ₂NH),5.25 (1H, m, CHOCO), 5.35 (1H, m, OCOCHPh), 7.45 (2H, d, Ar), 7.60 (5H,m, Ar), 7.80 (2H, d, Ar), 10.00-10.10 (2H, br s), 10.50 (1H, s).

Stage 6: Saponification of Cyclopentyl Ester

Stage 4 resin (2.5 g, loading, 0.94 mmol, 2.35 mmol) was suspended inMeOH (8.7 ml) and THF (8.7 ml). An aq. solution of 2.7 N NaOH (8.8 ml,10 eq, 23.5 mmol) was added. The mixture was shaken for 36 h. LCMS ofthe test cleave confirmed the completion of reaction, m/z 528 [M⁺+H]⁺.The resin was filtered and washed with water x 2, MeOH x 2, followed bythe standard wash procedure. The resin was dried under vacuum.

Stage 7:(S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid (21)

Stage 6 resin (2.5 g, loading 0.94 mmol, 2.35 mmol) was cleaved and bocdeprotected using the procedure outlined for Stage 5. The crude product(0.40 g) was purified by preparative HPLC giving compound (21) as theTFA salt. LCMS purity 100%, m/z 428 [M⁺+H], ¹H NMR (400 MHz, CD₃OD), δ:1.30 (4H, 2×CH₂), 1.55 (4H, 2×CH₂), 2.00 (2H, t, CH₂), 2.30 (2H, t,CH₂), 3.90 (1H, s, NHCH₂), 4.05 (2H, dd, NHCH₂ ), 4.95 (1 H, s, CHPh),7.35 (2H, d, Ar), 7.40 (5H, m, Ar), 7.55 (2H, d, Ar).

Synthesis of Compound (22) and Compound (23)

Stage 1: (S)-(4-Nitro-benzenesulfonylamino)-phenyl-acetic acid

To a solution of L-phenylglycine (0.227 g, 1.5 mmol) in water (5 ml) anddioxane (5 ml) was added triethylamine (0.42 ml, 3.0 mmol) followed byslow addition of 4-nitrobenzene sulphonyl chloride (0.5 g, 2.3 mmol) indioxane (5 ml) at 0° C. After stirring for 45 minutes the reactionmixture was evaporated to dryness, re-dissolved in EtOAc and washed withsaturated NaHCO₃ solution (2×20 ml) and water (10 ml). The EtOAc layerwas dried over Na₂SO₄, filtered and evaporated to dryness. LCMS purity75%, (molecular ion not observed) yield 0.58 g, (76%). This material wasused without any purification.

Stage 2: (S)-(4-Nitro-benzenesulfonylamino)-phenyl-acetic acidcyclopentyl ester

To a solution of stage 1 acid (4.32 g, 12.8 mmol) in cyclopentanol (60ml) at 0° C. was added slowly thionyl chloride (9.3 ml, 128 mmol). Thereaction mixture was stirred and heated under reflux at 70° C. for 2hours. The excess thionyl chloride was removed by evaporation in vacuo,the reaction mixture was extracted into EtOAc and washed with saturatedNaHCO₃ solution and dried over Na₂SO₄, filtered and evaporated todryness. Flash column chromatography purification with DCM gave therequired product (3.6 g, 70% yield). LCMS purity of 100%, (molecular ionnot observed).

Stage 3: (S)-(4-Amino-benzenesulfonylamino)-phenyl-acetic acidcyclopentyl ester

A mixture of (S)-(4-Nitro-benzenesulfonylamino)-phenyl-acetic acidcyclopentyl ester (5.29 g, 13.1 mmol) and 10% Pd/C (5.0 g) in EtOAc (350ml) was hydrogenated under balloon pressure at room temperature for 24h. The Pd/C catalyst was filtered off through a pad of celite. Thefiltrate was concentrated under reduced pressure to yield the requiredproduct (4.54 g, 92% yield). LCMS purity 100%, m/z 375 [M⁺+H]⁺.

Stage 4: Coupling of Anline

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (0.39g, loading 1.14 mmol/g) was swollen in anhydrous DCM (25 ml) and at 0°C. under N₂ atmosphere 1-chloro-N,N, 2-trimethylpropenylamine (0.175 ml,1.33 mmol) added dropwise. The reaction mixture was shaken for 1.5hours. A solution of stage 3 aniline (0.5 g, 1.33 mmol) in DCM (25 ml)was added followed by triethylamine (0.25 ml, 1.76 mmol). The reactionmixture was shaken for a further 10 minutes. LCMS after a test cleaveshowed 61% conversion, m/z 546 [M⁺+H]⁺. The resin was filtered andwashed using the standard wash procedure. The resin was dried undervacuum and used in the next step.

Stage 5:(S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzenesulfonylamino]-phenyl-aceticacid cyclopentyl ester (22)

Stage 4 resin (1.12 g, loading 1.14 mmol/g) was gently shaken in 2%TFA/DCM (10 ml) for 20 mins. The resin was filtered. The filtrate wascollected and evaporated under reduced pressure at room temperature. Theresin was re-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered.The combined filtrates were evaporated to dryness under reduced pressureat room temperature to give a residue. The residue was purified bypreparative HPLC to yield compound (22). LCMS purity 93%, m/z 546[M⁺+H]⁺, ¹H NMR (400 MHz, DMSO), δ: 1.20-1.68 (16H, m, 8×CH₂), 1.93 (2H,t, CH₂), 2.33 (2H, t, CH₂), 4.80 (1H, m, CHOCO), 4.81 (1H, d, OCOCHPh),7.27 (5H, m, Ar), 7.65 (2H, d, Ar), 7.71 (2H, d, Ar), 8.67 (1H, brs),8.75 (1H, d), 10.24 (1H, s), 10.34 (1H, s).

Stage 6: Saponification of Cyclopentyl Ester

Stage 4 resin (1.2 g, loading 1.14 mmol/g) was suspended in THF (8 ml)and methanol (8 ml) and 2.7M sodium hydroxide (5.1 ml, 13.68 mmol) wasadded. The mixture was shaken for 48 h. LCMS of the test cleaveconfirmed the completion of reaction, m/z 478 [M⁺+H]⁺. The resin wasfiltered and washed with water×2, MeOH×2, followed by the standard washprocedure. The resin was dried under vacuum.

Stage 7:(S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzenesulfonylamino]-phenyl-aceticacid (23)

Stage 6 resin (1.2 g, loading 1.14 mmol/g) was gently shaken in 2%TFA/DCM (10 ml) for 20 mins. The resin was filtered. The filtrate wascollected and evaporated under reduced pressure at room temperature. Theresin was re-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered.The combined filtrates were evaporated to dryness under reduced pressureat room temperature to give a residue. The residue was purified bypreparative HPLC to yield compound (23). LCMS purity 91%, m/z 478[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.44 (4H, m, 2×CH₂), 1.62-1.74 (4H,m, 2×CH₂), 2.12 (2H, t, CH₂), 2.34 (1H, m, OCOCHPh), 2.41 (2H, t, CH₂),7.25 (5H, m, Ar), 7.69 (2H, d, Ar), 7.72 (2H, d, Ar).

Synthesis of Compounds (24) and Compound (25)

Stage 1: (2,3,4,9-Tetrahydro-1H-beta-carbolin-6-yloxy)-acetic acidmethyl ester

A mixture of 5-carboxymethoxy tryptamine (1.24 g, 4.56 mmol), 36% aqformaldehyde and MeOH (25 ml) was heated under reflux for 1.5 h. Thereaction mixture was evaporated to dryness. MeOH (50 ml) and TMSCl (1.24ml) were sequentially added. Reflux was continued for 1 h. Reactionmixture was evaporated to dryness and was used in the next stage withoutpurification.

Stage 2: Amidation

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (2.0 g,loading 1.14 mmol/g, 2.28 mmol) was suspended in DCM (40 ml). pyBOP(3.56 g) was added followed by a DCM solution (40 ml) of Stage 1 amine(4.56 mmol) and DIPEA (3.9 ml, 22.8 mmol). The reaction was shaken atroom temperature for 18 h. LCMS after test cleave confirmed thecompletion of reaction. The resin was filtered and washed using thestandard wash procedure and was thoroughly dried.

Stage 3: Saponification of Methyl Ester

Stage 2 resin (2.0 g, 1.14 mmol/g, 2.28 mmol) was suspended in a mixtureof THF (10 ml) and MeOH (10 ml). 1.4M NaOH (10 ml) was added over 5 min.The mixture was shaken for 18 h. LCMS after test cleave confirmed thecompletion of reaction. The resin was filtered and washed using thestandard wash procedure.

Stage 4: Coupling with L-phenylglycine cyclopentyl ester

Stage 3 resin (2.0 g, loading 1.14 mmol/g, 2.28 mmol) was suspended inDCM (30 ml). pyBOP (3.56 g, 6.84 mmol) was added, followed byL-phenylglycine cyclopentyl ester (2.59 g, 6.84 mmol) and DIPEA (3.9 ml,22.8 mmol). The mixture was shaken for 18 h. LCMS after test cleaveconfirmed completion of reaction. The resin was filtered, washed usingstandard wash procedure and dried under vacuum.

Stage 5:(S)-{2-[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carbolin-6-yloxy]-acetylamino}-phenyl-aceticacid cyclopentyl ester (24)

Stage 4 resin (0.8 g, loading 1.14 mmol/g, 0.91 mmol) was cleaved using2% TFA/DCM (3×10 ml). The filtrate was evaporated to dryness at roomtemperature under reduced pressure to give an oily residue (200 mg)which was purified by preparative HPLC to give compound (24) as the TFAsalt. LCMS purity 95%, m/z 619 [M⁺+H]⁺, ¹H NMR (400 MHz, DMSO), δ:1.05-1.66 (16H, m, 8×CH₂), 1.79 (2H, m, CH₂), 2.16-2.31 (2 H, m,2.41-2.56 (2H, m, CH₂), 3.60 (2H, m, CH₂), 4.42 (2H, s, CH₂), 4.49 (2H,s, CH₂), 4.93 (1H, m, CHOCO), 5.28 (1H, m, OCOCHPh), 6.59 (1H, d, Ar),6.65 (1H, s, Ar), 7.04 (1H, d, Ar), 7.21 (5H, m, Ar), 8.57 (1H, m),10.17 (1H, s), 10.58 (1H, s, Ar).

Stage 6: Saponification of Cyclopentyl Ester

Stage 4 resin (1.0 g, loading 1.14 mmol/g, 1.14 mmol) was saponifiedaccording to the procedure described in Stage 3.

Stage 7:(S)-{2-[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carbolin-6-yloxy]-acetylamino}-phenyl-aceticacid cyclopentyl ester (25)

Stage 6 resin (1.0 g, loading 1.14 mmol/g, 1.14 mmol) was cleaved andpurified using the procedure detailed in stage 5. Compound (25): LCMSpurity 97%, m/z 551 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.33-1.49 (4H,m, 2×CH₂), 1.58-1.75 (4H, m, 2×CH₂), 2.06-2.17 (2H, m, CH₂), 2.51-2.60(2H, m, CH₂), 2.70-2.83 (2H, m, CH₂), 3.85-3.96 (2H, m, CH₂), 4.61 (2H,m, CH₂), 4.78 (2H, m, CH₂), 5.56 (1H, s, OCOCHPh), 6.89 (1H, m, Ar),7.00 (1H, s, Ar), 7.26 (1H, m, Ar), 7.35 (5H, m, Ar).

Synthesis of Compounds in FIG. 2 as Exemplified by Compound (26) andCompound (27)

Synthesis of Compound (26) and Compound (27)

Stage 1: (S)-2-(3-Nitro-benzylamino)-3-phenyl-propionic acid ethyl ester

3-Nitrobenzyl bromide (10.0 g, 46 mmol) was dissolved in DMF (180 ml)and potassium carbonate (12.7 g, 92 mmol) added, followed byL-phenylalanine ethyl ester hydrochloride (10.6 g, 46 mmol). Thereaction was stirred for 17 h at room temperature before evaporating todryness. The residue was re-dissolved in EtOAc (150 ml) and washed withwater (3×80 ml), dried (Na₂SO₄) filtered and concentrated to dryness.After purification by flash column chromatography (30% EtOAc/hexane) theproduct was obtained (3.7 g, 24% yield). LCMS purity 86%, m/z 329[M⁺+H]⁺.

Stage 2:(S)-2-[tert-Butoxycarbonyl-(3-nitro-benzyl)-amino]-3-phenyl-propionicacid ethyl ester

Stage 1 amine (13.4 g, 40.9 mmol) was dissolved in THF (250 ml) beforeaddition of potassium carbonate (8.46 g, 61.4 mmol) and water (150 ml).Di-^(t)butyl-dicarbonate (35.6. 163 mmol) was added and the reactionmixture heated to 50° C. for 18 h. DCM was added the resultant mixturewashed consecutively with 0.1 M HCl (150 ml), sat. aq. NaHCO₃ and water(150 ml). The DCM layer was dried (Na₂SO₄), filtered and concentrated todryness. After purification by flash column chromatography (5%EtOAc/hexane) the product was isolated (9.4 g, 54% yield). LCMS purity95%, m/z 428 [M⁺+H]⁺.

Stage 3:(S)-2-[(3-Amino-benzyl)-tert-butoxycarbonyl-amino]-3-phenyl-propionicacid ethyl ester

Stage 2 carbamate (4.92 g, 11.5 mmol) was dissolved in EtOAc (150 ml)before addition of Pd/C (10% wet) catalyst (0.8 g) and hydrogenatedunder balloon pressure at room temperature for 18 h. The reactionmixture was filtered through a pad of celite and evaporated to drynessto give a red solid (4.0 g, 89% yield). LCMS purity 100%, m/z 399[M⁺+H]⁺.

Stage 4: Coupling to Resin

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (1.0 g,loading 0.83 mmol/g) was swollen in DMF (15 ml) and PyBOP (1.36 g, 2.61mmol) added, followed by DIPEA (1.5 ml, 8.7 mmol). Stage 3 aniline (1.04g, 2.61 mmol) was dissolved in DCM (15 ml) and added to the reactionmixture. The reaction was shaken for 24 h at room temperature. LCMSafter a test cleave indicated 86% conversion, m/z 570 [M⁺+H]⁻. The resinwas filtered and washed using the standard wash procedure. The resin wasdried under vacuum.

Stage 5:(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-3-phenyl-propionicacid ethyl ester (26)

Stage 4 resin (1.3 g, loading 0.83 mmol) was gently shaken in 2% TFA/DCM(10 ml) for 20 mins. The resin was filtered. The filtrate was evaporatedunder reduced pressure at room temperature. The resin was re-treatedwith 2% TFA/DCM (10 ml) and was filtered after 20 mins. The combinedfiltrates were evaporated to dryness under reduced pressure at roomtemperature to give an oily residue. The residue was allowed to stand in20% TFA/DCM for 40 mins. After evaporation to dryness, also underreduced pressure at room temperature, the crude product was purified bypreparative HPLC to yield compound (26). LCMS purity 100%, m/z 470[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.08 (3H, t, CH₃), 1.35-1.45 (4H, m,2×CH₂), 1.60-1.80 (4H, m, 2×CH₂), 2.10 (2H, t, CH₂), 2.40 (2H, t, CH₂),3.13 (1H, dd, PhCHH), 3.40 (1H, dd, PhCHH), 4.11 (2H, q, CH₂ CH₃),4.14-4.22 (3H, m), 7.20-7.48 (8H, m, Ar), 7.92 (1H, s, Ar).

Stage 6: Saponification

Stage 4 resin (1.4 g, loading 0.83 mmol) was suspended in THF (8.6 ml)and methanol (8.6 ml) and 1.4M sodium hydroxide solution (8.6 ml, 5.98mmol) was added. The mixture was shaken for 24 hours before testcleavage revealed 83% conversion to required acid, m/z 541 [M⁺+H] Theresin was filtered and washed with water×2, MeOH×2, followed by thestandard wash procedure. The resin was dried under vacuum.

Stage 7:(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-3-phenyl-propionicacid (27)

Stage 6 resin (1.44 g, loading 0.83 mmol) was gently shaken in 2%TFA/DCM (10 ml) for 20 mins. The resin was filtered. The filtrate wasevaporated under reduced pressure at room temperature. The resin wasre-treated with 2% TFA/DCM (10 ml) and was filtered after 20 mins. Thecombined filtrates were evaporated to dryness under reduced pressure atroom temperature to give an oily residue. The residue was allowed tostand in 20% TFA/DCM for 40 mins. After evaporation to dryness, underreduced pressure at room temperature, the crude product was purified bypreparative HPLC to yield compound (27). LCMS purity 100%, m/z 442[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.35-1.48 (4H, m, 2×CH₂), 1.60-1.78(4H, m, 2×CH₂), 2.10 (2H, t, CH₂), 2.40 (2H, t, CH₂), 3.20 (1H, dd,PhCHH), 3.28 (1H, dd, PhCHH), 3.90 (1H, t, OCOCH), 4.14 (2H, m), 7.15(1H, d, Ar), 7.26 (6H, m, Ar), 7.51 (1H, d, Ar), 7.73 (1 H s, Ar).

The following compounds were prepared according to the proceduredescribed for compound (26) and compound (27)

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-3-phenyl-propionicacid cyclopentyl ester (28)

LCMS purity 100%, m/z 510 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.00-1.61(16H, m, 8×CH₂), 1.90 (2H, t, CH₂), 2.20 (2H, d, CH₂), 2.90 (1H, dd,PhCHH), 3.20 (1H, dd, PhCHH), 4.00-4.11 (3H, m), 4.91 (1H, m), 7.00-7.25(8H, m, Ar), 7.75 (1H, s, Ar).

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-phenyl-butyricacid ethyl ester (29)

LCMS purity 100%, m/z 484 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.23-1.29(7H, m, CH₃, 2×CH₂), 1.53 (2H, t, CH₂), 1.62 (2H, t, CH₂), 1.99 (2H, t,CH₂), 2.11-2.16 (2H, m, CH₂), 2.28 (2H, t, CH₂), 2.53-2.61 (1H, m, CH),2.65-2.76 (1H, m, CH), 3.80-3.90, (1H, m, CHCO₂Et), 4.05 (2H, s, CH₂),4.21 (2H, q, CH₂), 7.05-7.15 (4H, m, Ar), 7.15-7.22 (2H, m, Ar),7.25-7.39 (2H, m, Ar), 7.75 (1H, s, Ar).

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-phenyl-butyricacid (30)

LCMS purity 100%, m/z 456 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.27-1.32(4H, m, 2×CH₂), 1.53 (2H, t, CH₂), 1.62 (2H, t, CH₂), 1.99 (2H, t, CH₂),2.11-2.16 (2H, m, CH₂), 2.29 (2H, t, CH₂), 2.57-2.64 (1H, m, CH),2.69-2.77 (1H, m, CH), 3.84-3.87 (1 H, m, CHCO₂H), 4.12 (2H, q, CH₂),7.09-7.11 (4H, m, Ar), 7.16-7.20 (2H, m, Ar), 7.27-7.35 (2H, m, Ar),7.78 (1H, s, Ar).

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-phenyl-butyricacid cyclopentyl ester (31)

LCMS purity 100%, m/z 524 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20-1.35(4H, m), 1.45-1.62 (10H, m), 1.85 (2H, m), 2.00 (2H, t, CH₂), 2.10 (2H,m), 2.28 (2H, t, CH₂), 2.55 (1H, m), 2.68 (1H, m), 3.88 (1H, t,OCOCHNH), 4.11 (2H, s, CH₂ Ph), 5.24 (1H, m) 7.02-7.12 (4H, m, Ar), 7.18(2H, m, Ar), 7.30 (2H, m, Ar), 7.80 (1H, s, Ar).

(S)-3-tert-Butoxy-2-[3-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-propionicacid ethyl ester (32)

LCMS purity 90%, m/z 466 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.25 (9H,s, C(CH ₃)₃), 1.35 (3H, t, CH₂CH ₃), 1.35-1.45 (4H, m, 2×CH₂), 1.62-1.76(4H, m, 2×CH₂), 2.12 (2H, t, CH₂), 2.40 (2H, t, CH₂), 3.89 (1H, m), 3.98(1H, m), 4.20-4.40 (5 H, m), 7.25 (1H, d, Ar), 7.39-7.50 (2H, m, Ar),7.90 (1H, s, Ar).

(S)-3-tert-Butoxy-2-[3-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-propionicacid (33)

LCMS purity 86%, m/z 438 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20 (9H,s, C(CH ₃)₃), 1.38 (4H, m, 2×CH₂), 1.57-1.75 (4H, m^(, 2)×CH₂), 2.10(2H, t, CH₂), 2.39 (2H, t, CH₂), 3.78-3.85 (3H, m), 4.26 (2H, s, CH₂Ph),7.21 (1H, d, Ar), 7.39 (1H, t, Ar), 7.50 (1H, d, Ar), 7.80 (1H, s, Ar).

(S)-3-tert-Butoxy-2-[3-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-propionicacid cyclopentyl ester (34)

LCMS purity 94%, m/z 506 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.25 (9H,s, C(CH ₃)₃), 1.33-1.50 (4H, m, 2×CH₂), 1.60-2.00 (12H, m), 2.13 (2H, t,CH₂), 2.42 (2 H, t, CH₂), 3.83-4.00 (2H, m), 4.18 (1H, m), 4.28 (2H, s,CH₂Ph), 5.35 (1H, m), 7.25 (1H, m, Ar), 7.45 (2H, m, Ar), 7.90 (1H, s,Ar).

(S)-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid tert-butyl ester (35)

LCMS purity 97%, m/z 484 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.30 (13H,m, 2×CH₂, C(CH ₃)₃), 1.45-1.65 (4H, m, CH₂X₂), 1.93-2.05 (2H, m, CH₂),2.20-2.40 (2H, m, CH₂), 3.99 (2H, q, CH₂), 4.65-4.95 (1H, m, CH, maskedsignal) 7.05 (1H, d, Ar), 7.25-7.33 (2H, m, Ar), 7.35-7.50 (5H, m, Ar),7.75 (1H, s, Ar).

(S)-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid cyclopentyl ester (36)

LCMS purity 100%, m/z 496 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.30-1.70(16H, m, 8×CH₂), 2.00 (2H, t, CH₂), 2.30 (2H, t, CH₂), 4.05 (2H, dd, CH₂NH), 5.00 (1H, m, OCOCHPh), 5.15 (1H, m, CHOCO), 7.05 (1H, m, Ar), 7.30(2H, m, Ar), 7.40 (5H, m, Ar), 7.75 (1H, m, Ar).

(S)-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid (37)

LCMS purity 100%, m/z 428 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20-1.35(4H, m, 2×CH₂), 1.50-1.65 (4H, m, 2×CH₂), 2.00 (2H, m, CH₂), 2.30 (2H,m, CH₂), 4.00 (2 H, dd, CH₂ NH), 4.90 (1H, m, OCOCHPh), 7.05 (1H, m,Ar), 7.25-7.50 (7H, m, Ar), 7.70 (1H, m, Ar).

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-methyl-pentanoicacid (38)

LCMS purity 91%, m/z 408 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 0.78 (3H,d, J=6.6 Hz, CH₃), 0.84 Hz (3H, d, J=6.6 Hz, CH₃), 1.26-1.40 (6H, m,alkyl), 1.49-1.70 (5H, m, CH+2×CH₂), 1.95 (2H, t, J=7.32, CH₂), 2.25(2H, t, J=7.36, CH₂), 3.00 (1H, t, J=6.88 Hz, NHCHCO), 3.42 (1H, d,J=12.7 Hz, CH), 3.68 (1H, d, J=12.5 Hz, CH), 7.00 (1H, d, J=7.6 Hz, Ar),7.15 (1H, t, J=7.8 Hz, Ar), 7.30 (1H, s. Ar), 7.47 (1H, brd, Ar)

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-methyl-pentanoicacid cyclopentyl ester (39)

LCMS purity 100%, m/z 476 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 0.85-0.95(6H, 2×d, 2×CH₃), 1.30 (4H, m, 2×CH₂), 1.50-1.70 (13H, m, alkyl), 1.75(2H, m, CH₂), 2.00 (2H, t, CH₂), 2.30 (2H, t, CH₂), 3.90 (1H, NHCHCO),4.10 (2H, q, CH₂), 5.25, (1H, m, CH), 7.10 (1H, d, Ar), 7.30 (2H, m),7.80 (1H, s, Ar)

Synthesis of Compound (40) and Compound (41)

Stage 1: (S)-(2-Nitro-benzylamino)-phenyl-acetic acid cyclopentyl ester

A mixture of 2-nitrobenzyl bromide (15 g, 69.4 mmol), L-phenylglycinecyclopentyl ester tosyl salt (27.2 g, 69.4 mmol) and potassium carbonate(19.2 g, 138.8 mmol) in DMF (300 ml) was stirred at room temperature for18 h. The reaction mixture was diluted with EtOAc (300 ml) and washedwith water (3×200 ml). The EtOAc layer was isolated, dried (Na₂SO₄),filtered and concentrated to dryness yielding an orange coloured oil. Acrude weight of 24 g was isolated. LCMS purity 81%, m/z 355 [M⁺+H]⁺.This product was used without further purification

Stage 2: (S)-[tert-Butoxycarbonyl-(2-nitro-benzyl)-amino]-phenyl-aceticacid cyclopentyl ester

To a solution of (S)-(2-Nitro-benzylamino)-phenyl-acetic acidcyclopentyl ester (24.4 g, 69.1 mmol) in THF (150 ml) was added K₂CO₃(7.6 g, 69.1 mmol), followed by di-tert-butyl dicarbonate (30.1 g, 138.1mmol). Water (150 ml) was added and the reaction stirred at roomtemperature for 8 days with further di-tert-butyl dicarbonate (45.1 g,206.6 mmol). The reaction mixture was evaporated to dryness. The residuewas re-dissolved in EtOAc (300 ml), washed with 0.1 M HCl (150 ml), sat.aq.NaHCO₃ and water (150 ml). The EtOAc layer was dried (Na₂SO₄),filtered and concentrated to dryness yielding a yellow oil. Afterpurification by column chromatography (20% EtOAc/hexane) the product wasobtained as clear yellow oil (15 g, 48% yield).

Stage 3: (S)-[(2-Amino-benzyl)-tert-butoxycarbonyl-amino]-phenyl-aceticacid cyclopentyl ester

A mixture of stage 2 carbamate (4.44 g, 9.78 mmol) and 10% Pd/C (0.7 g)in EtOAc (130 ml) was hydrogenated at room temperature for 18 h underballoon pressure. The Pd/C catalyst was filtered off through a pad ofcelite. The filtrate was concentrated under reduced pressure to yield awhite solid (4.25 g). LCMS purity 100%, m/z 425 [M⁺+H]⁺,

Stage 4: Coupling of Stage 3 Aniline

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (1.6 g,loading 0.83 mmol) was swollen in anhydrous DCM (100 ml).1-Chloro-N,N-2-trimethylpropenylamine (Ghosez reagent)¹ (0.56 ml, 3.3mmol, 3 eq) was added at 0° C. under the atmosphere of N₂. The mixturewas allowed to warm to room temperature and gently shaken for 1-2 h.Stage 3 aniline (1.4 g, 3.3 mmol, 3 eq) was added portionwise over 20min. Et₃N (0.76 ml, 4.4 mmol, 4 eq) was added. The mixture was shakenfor 1 h. LCMS after a test cleave shows 97% conversion, m/z 596 [M⁺+H]⁺.The resin was filtered and washed using the standard wash procedure. Theresin was dried under vacuum.

-   -   1. Ghosez et al, J. C. S. Chem. Comm., 1979, 1180.

Stage 5:(S)-[2-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid cyclopentyl ester (40)

Stage 4 resin (1.34 g, loading 0.83 mmol) was gently shaken in 2%TFA/DCM (10 ml) for 20 mins. The resin was filtered. The filtrate wascollected and evaporated under reduced pressure at room temperature. Theresin was re-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered.The combined filtrates were evaporated to dryness under reduced pressureat room temperature to give a residue. This residue was allowed to standin 20% TFA/DCM for 40 mins. After evaporation to dryness, also underreduced pressure at room temperature, the residue was purified bypreparative HPLC to yield compound 40 as the TFA salt, LCMS purity 100%,m/z 496 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.40-2.00 (16H, m, 8×CH₂),2.15 (2H, m, CH₂), 2.45 (2 H, m, CH₂), 3.95 (1H, d, CH ₂NH), 4.20 (1H,d, CH₂ NH), 5.20 (1H, m, OCOCHPh), 5.35 (1H, m, CHOCO), 7.25 (1H, m,Ar), 7.40 (1H, m, Ar), 7.50-7.60 (7H, m, Ar).

Stage 6: Saponification

Stage 4 resin (2.0 g, loading, 0.83 mmol, 2.35 mmol) was suspended inMeOH (6.1) and THF (6.1 ml). 2.7 N NaOH (aq, 6.1 ml) was added. Themixture was shaken for 5 days. LCMS of the test cleave confirmed thecompletion of reaction, m/z 528 [M⁺+H]⁺. The resin was filtered andwashed with water x 2, MeOH x 2, followed by the standard washprocedure. The resin was dried under vacuum.

Stage 7:(S)-[2-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid compound (41)

Stage 6 resin (2.0 g, loading 0.83 mmol) was cleaved and boc deprotectedusing the procedure outlined for stage 5. The crude product was purifiedby preparative HPLC yielding compound (41) as the TFA salt. LCMS purity98%, m/z 428 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.25-1.35 (4H, m,2×CH₂), 1.50-1.65 (4H, m, 2×CH₂), 2.00 (2 H, m, CH₂), 2.30 (2H, m, CH₂),3.80 (1H, d, CH₂ NH), 4.10 (1H, d, CH₂ NH), 5.00 (1 H, m, OCOCHPh), 7.10(1H, m, Ar), 7.30 (1H, m, Ar), 7.40-7.50 (7H, m, Ar).

Synthesis of Compound (42) and Compound (43)

Stage 1: 1,3,4,9-Tetrahydro-beta-carboline-1,2-dicarboxylic acid2-benzyl ester

A solution of 1,2,3,4-tetrahydrocarboline-1-carboxylic acid (5 g, 23.1mmol) in dioxane (25 ml) and 2M NaOH (23 ml, 46 mmol) was cooled to 0°C. Benzyl chloroformate (3.95 ml, 27 mmol) was added slowly. Afterstirring at room temperature for 1 h further benzyl chloroformate (1.4ml, 9.5 mmol) was added. After 2.5 h the reaction mixture was washedwith ether The aqueous layer was acidified to pH 2 and extracted withDCM, dried (MgSO₄), filtered and evaporated to dryness yielding a firstcrop of material as a yellow solid with LCMS purity of 79%, m/z 351[M⁺+H]⁺. The initial crop was used without further purification. Asecond crop of material was obtained following concentration of theether layers to give further crude product. The crude material waspurified by flash chromatography eluting with DCM to 20% 2M methanolicNH₃, 80% DCM yielding further Cbz-protected compound (yield 49%) at LCMSpurity 82%, m/z 351 [M⁺+H]⁺.

Stage 2:1-(Methoxy-methyl-carbamoyl)-1,3,4,9-tetrahydro-beta-carboline-2-carboxylicacid benzyl ester

1,3,4,9-Tetrahydro-beta-carboline-1,2-dicarboxylic acid 2-benzyl ester(3 g, 8.4 mmol) was dissolved in anhydrous DCM (30 ml) and triethylamine(5.22 ml, 37.8 mmol) added. To this solution was added HOBt (2.848 g,21.4 mmol), EDCI (4.08 g, 21.4 mmol) and N, O-dimethylhydroxylaminehydrochloride (1.86 g, 19.1.mmol). After stirring at room temperaturefor 2 h the reaction mixture was evaporated to dryness, re-dissolved inEtOAc and washed with saturated NaHCO₃ solution (2×100 ml) and water (50ml). The EtOAc layer was dried (Na₂SO₄), filtered and evaporated todryness. Purification by column chromatography using DCM to 3%methanol/DCM gave the required Weinreb amide (yield 40%). LCMS purity85%, m/z 394 [M⁺+H]⁺.

Stage 3: 1-Formyl-1,3,4,9-tetrahydro-beta-carboline-2-carboxylic acidbenzyl ester

A solution of 1,3,4,9-tetrahydro-beta-carboline-1,2-dicarboxylic acid2-benzyl ester (3.7 mg, 9.4 mmol) in THF (100 ml) under N₂ was cooled to−78° C. 1.5M DIBAL in toluene solution (31.2 ml, 47 mmol) was added over2 hours. After stirring for 4 hours the reaction mixture was quenchedwith methanol and water, extracted into EtOAc and washed with diluteaqueous HCl. The organic layer was dried over Na₂SO₄, filtered andevaporated to dryness. LCMS purity 50%, m/z 335 [M⁺+H]⁺ The material wasused in the next stage without further purification.

Stage 4 :1-{[((S)-Cyclopentyloxycarbonyl-phenyl-methyl)-amino]-methyl}-1,3,4,9-tetrahydro-beta-carboline-2-carboxylicacid benzyl ester

A mixture of 1-Formyl-1,3,4,9-tetrahydro-beta-carboline-2-carboxylicacid benzyl ester(1 g, 3 mmol), sodium acetate (0.68 g, 87.4 mmol),L-phenylglycine cyclopentyl ester tosyl salt (1.16 g, 3 mmol), sodiumcyanoborohydride (0.26 g, 4.2 mmol) and molecular sieves in IPA (100 ml)was stirred at room temperature for 1 hour. The reaction mixture wasevaporated to dryness, re-dissolved in EtOAc and washed sequentiallywith saturated NaHCO₃ solution and brine. The EtOAc layer was dried overMgSO₄, filtered and evaporated to dryness. LCMS purity of 39%, m/z 538[M⁺+H]⁺. The crude material was taken to the next stage without furtherpurification.

Stage 5:1-{[tert-Butoxycarbonyl-((S)-cyclopentyloxycarbonyl-phenyl-methyl)-amino]-methyl}-1,3,4,9-tetrahydro-beta-carboline-2-carboxylicacid benzyl ester

To a stirred solution of stage 4 amine (1.08 g, 2.0 mmol), in THF (20ml) was added potassium carbonate (0.42 g, 3.0 mmol) and di-tert-butyldicarbonate (1.75 g, 8.0 mmol). The reaction mixture was stirred at 50°C. for 96 hours and cooled to room temperature, diluted with DCM (50 ml)and washed with 0.1M HCl solution (25 ml), saturated NaHCO₃ solution(2×25 ml) and water (15 ml). The DCM layer was dried, Na₂SO₄, filteredand evaporated to dryness. Purification by column chromatography using10% EtOAc/heptane gave the product (0.89 g 70% yield). LCMS purity of79%, m/z 638 [M⁺+H]⁺.

Stage 6:(S)-[tert-Butoxycarbonyl-(2,3,4,9-tetrahydro-1H-beta-carbolin-1-ylmethyl)-amino]-phenyl-aceticacid cyclopentyl ester

A solution of stage 5 dicarbamate (0.5 g, 0.78 mmol) in ethanol (40 ml)was stirred under the atmosphere of hydrogen in the presence of 10% Pd/C(0.4 g) for 2 h under balloon pressure. The reaction mixture wasfiltered through a pad of celite and evaporated to dryness yielding therequired product (0.35 g, 90%), 91% purity by LCMS, m/z 504 [M⁺+H]⁺.

Stage 7: Coupling of stage 6 amine

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (703mg, loading 0.83 mmol/g) was swollen in DCM (12 ml). PyBOP (912 mg, 1.75mmol) was added, followed by stage 6 amine (325 mg, 0.64 mmol) and DIPEA(1.01 ml, 5.8 mmol). The reaction mixture was shaken for 18 hours. LCMSof material following test cleavage indicated 80% conversion m/z 675[M⁺+H]⁺. The resin was filtered and washed using the standard washprocedure. The resin was dried under vacuum.

Stage 8:(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carbolin-1-ylmethyl]-amino}-phenyl-aceticacid cyclopentyl ester (42)

Stage 7 resin (135 mg, loading 0.83 mmol) was gently shaken in 2%TFA/DCM (10 ml) for 20 mins. The resin was filtered. The filtrate wasevaporated under reduced pressure at room temperature. The resin wasre-treated with 2% TFA/DCM (10 ml) and was filtered after 20 mins. Thecombined filtrates were evaporated to dryness under reduced pressure atroom temperature to give an oily residue. The residue was allowed tostand in 20% TFA/DCM for 40 mins. After evaporation to dryness, alsounder reduced pressure at room temperature, the crude product waspurified by preparative HPLC to yield compound (42) as the TFA salt,LCMS purity 91%, m/z 575 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.30-1.70(16H, m, 8×CH₂), 2.00 (2H, m, CH₂), 2.50 (2H, m, CH₂), 2.75 (2H, m,CH₂), 3.30-3.50 (2H, m, CH₂), 4.15 (1H, m, CH₂CH), 4.80 (2H, m, CH₂ NH,masked signal), 5.25 (1H, m, CHOCO), 6.00 (1H, m, OCOCHPh), 6.90 (1H, m,Ar), 7.00 (1H, m, Ar), 7.20 (1H, m, Ar), 7.30 (1H, m, Ar), 7.45 (5H, m,Ar).

Stage 9: Saponification of Cyclopentyl Ester

Stage 7 resin (395 mg, loading 0.83 mmol) was suspended in THF (1.5 ml)and methanol (1.5 ml) and 1.4M sodium hydroxide (aq) solution (1.17 ml,1.6 mmol) was added. The mixture was shaken for 8 days. Test cleavageindicated 86% conversion to the acid, m/z 607 [M⁺+H]. The resin wasfiltered and washed with water×2, MeOH×2, followed by the standard washprocedure. The resin was dried under vacuum.

Stage 10:(S)-{[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carbolin-1-ylmethyl]-amino}-phenyl-aceticacid (43)

Stage 9 resin (100 mg, loading 0.83 mmol) was cleaved and bocdeprotected using the procedure outlined for compound (42). Purificationby preparative HPLC afforded compound (43) as the TFA salt, LCMS purity96%, m/z 507 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.25-1.40 (4H, m,2×CH₂), 1.50-1.65 (4H, m, 2×CH₂), 2.00 (2 H, m, CH₂), 2.50 (2H, m, CH₂),2.70 (2H, m, CH₂), 3.40 (2H, m, CH₂), 4.15 (1H, m, CH₂CH), 4.80 (2H, m,CH₂ NH, masked signal), 6.00 (1H, m, OCOCHPh), 6.90 (1H, m, Ar), 7.00(1H, m, Ar), 7.20 (1H, m, Ar), 7.30-7.50 (6H, m, Ar).

Synthesis of Compounds in FIG. 3 as Exemplified by Compound (44) andCompound (45)

Preparation of Building Blocks H-L

Building block H

(S)-1,2,3,4-Tetrahydroisoquinoline-3-carboxylic acid (10 g, 56 mmol),TMSCl (39 ml, 310 mmol) and methanol (500 ml) were refluxed together (at70° C.) for 2 hours. The reaction mixture was evaporated to dryness andLCMS analysis indicated 100% conversion to(S)-1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid methyl ester, m/z192 [M⁺+H]⁺.

Building Block I

DL-Proline (10 g, 87 mmol), TMSCl (51 ml, 430 mmol) and methanol (500ml) were refluxed together (at 70° C.) for 2 hours. The reaction mixturewas evaporated to dryness and LCMS analysis indicated 100% conversion todesired product pyrrolidine-2-carboxylic acid methyl ester, m/z 130[M⁺+H]⁺.

Building Block J

Stages 1 & 2

(R)-2-Fmoc-1,2,3,4-tetrahydronorharmane-3-carboxylic acid (2.0 g, 9.25mmol) was added to solution of TMSCl (6 ml, 47.17 mmol) in methanol (100ml) and heated under reflux for 2 hours. The reaction mixture wasevaporated to dryness to give 1.7 g product (100% conversion by LCMS,m/z 453 [M⁺+H]⁺). Stage 1 ester (1.7 g) was treated with 20% piperidinein DCM (100 ml) for 30 minutes to effect fmoc removal. The crudereaction mixture was evaporated to dryness, dissolved in DCM and washedwith saturated NaHCO₃ solution. The DCM layer was isolated, dried(Na₂SO₄), filtered and concentrated to dryness. Purification by columnchromatography was carried out using 3% MeOH/DCM to give(S)-2,3,4,9-tetrahydro-1H-beta-carboline-4-carboxylic acid methyl ester.LCMS 100%, m/z 231 [M⁺+H]⁺.

Building Block K

Meythl-3-aminobenzoate was obtained from commercial sources BuildingBlock L

Stage 1

A solution of glyoxylic acid monohydrate (1.51 g, 16.4 mmol) in water(10 ml) was added dropwise to a stirred solution of tryptamine.HCl (3.0g, 15.3 mmol) in water (200 ml). KOH (0.827 g, 14.7 mmol) in water (10ml) was added. The reaction mixture was stirred at room temperature for1 h after which time precipitation occurred. Following filtration underreduced pressure the white precipitate was collected and washed withwater to furnish 2,3,4,9-tetrahydro-1H-beta-carboline-1-carboxylic acidYield 1.9 g (58%); m/z 217 [M⁺+H]⁺.

Stage 2

A solution of 1,2,3,4-tetrahydro-beta-carboline-1-carboxylic acid (7.4g) in MeOH (250 ml) was saturated with HCl gas for 20 min. The reactionmixture was gently stirred at room temperature for 18 h. The reactionmixture was re-treated with HCl gas and allowed to stir for a further 18h. Upon completion of the reaction the mixture was concentrated in vacuoto yield building block L, LCMS purity 95%, m/z 231 [M⁺H]⁺. The product(2,3,4,9-tetrahydro-1H-beta-carboline-1-carboxylic acid methyl ester)was used without further purification.

Synthesis of Compounds Outlined in FIG. 3 Exemplified by Compound (44, Rcyclopentyl) and compound (45, R═H)

Stage 1: Loading of Amine onto Resin

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (6.6 g,loading, 0.83 mmol) was swollen in anhydrous DCM (65 ml). PyBOP (8.6 g,16.43 mmol), amine building block A (3.7 g, 16.43 mmol) and DIPEA (9.5ml, 58.4 mmol) were added. The reaction was shaken for 24 hours at roomtemperature. LCMS of test cleaved material indicated reactioncompletion. The resin was filtered and washed using the standard washprocedure. The resin was dried under vacuum.

Stage 2: Saponification of Methyl Ester

Resin bound stage 1 ester (6.95 g, loading 0.83 mmol/g) was suspended inTHF (25 ml) and methanol (25 ml). Sodium hydroxide, 1.4M aqueoussolution (25 ml) was added. The mixture was shaken for 48 hours andfurther sodium hydroxide (25 ml) added after 24 hours. LCMS of the testcleaved material indicated 65% conversion to the acid m/z 349 [M⁺+H]⁺.The resin was filtered and washed with water×2, MeOH×2, followed by thestandard wash procedure. The resin was dried under vacuum.

Stage 3: Coupling with L-phenylglycine Cyclopentyl Ester

Resin bound stage 2 carboxylic acid (2.2 g, loading 0.83 mmol/g) wasswollen in anhydrous DCM (25 ml). PyBOP (2.85 g, 5.48 mmol),L-phenylglycine cyclopentyl ester tosyl salt (2.14 g, 5.48 mmol) andDIPEA (3.17 ml, 18.3 mmol) were added. The mixture was shaken for 24hours at room temperature. LCMS following test cleavage revealed 52%conversion, m/z 550 [M⁺+H]⁺. The resin was filtered and washed usingstandard wash procedure. The resin was dried under vacuum

Stage 4:(S)-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (44)

Stage 3 resin (2.2 g, loading 0.83 mmol) was gently shaken in 2% TFA/DCM(10 ml) for 20 mins. The resin was filtered. The filtrate was collectedand evaporated under reduced pressure at room temperature. The resin wasre-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered. Thecombined filtrates were evaporated to dryness under reduced pressure atroom temperature to give a residue. The residue was purified bypreparative HPLC to yield compound (44) as the TFA salt. LCMS purity95%, m/z 550 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.12-1.75 (16H, m,8×CH₂), 1.92-2.02 (2H, m, CH₂), 2.09-2.30 (1H, m), 2.48 (1H, m), 3.10(2H, m, CH₂), 4.58-4.66 (2H, m, CH₂), 4.82 (1H, m), 5.04 (1H, m), 5.20(1H, s, OCOCHPh), 6.95-7.20 (9H, m, Ar).

Stage 5—Saponification of Cyclopentyl Ester

Stage 3 resin (1.3 g, 1.13 mmol) was suspended in THF (4.6 ml) andmethanol (4.6 ml). Sodium hydroxide added as a 1.4M aqueous solution(4.6 ml). The mixture was shaken for 24 hours. LCMS of the test cleavedmaterial confirmed conversion to required acid. The resin was filteredand washed with water x 2, MeOH x 2, followed by the standard washprocedure. The resin was dried under vacuum.

Stage 6:(S)-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-phenyl-aceticacid (45)

Stage 5 resin (1.3 g, loading 0.83 mmol) was gently shaken in 2% TFA/DCM(10 ml) for 20 mins. The resin was filtered. The filtrate was collectedand evaporated under reduced pressure at room temperature. The resin wasre-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered. Thecombined filtrates were evaporated to dryness under reduced pressure atroom temperature to give a residue. The residue was purified bypreparative HPLC to yield compound (45). LCMS purity 96%, m/z 482[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.12-1.38 (4H, m, 2×CH₂), 1.45-1.61(4H, m, CH₂), 1.98 (2H, m, CH₂), 2.10-2.58 (2H, m, CH₂), 3.04-3.20 (2H,m, CH₂), 4.48-4.65 (2H, m), 4.85 (1H, m), 5.20 (1H, m), 6.92-7.25 (9H,m, Ar).

The following compounds were prepared according to the proceduredescribed for compounds (44) and compound (45)

(S)-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-phenyl-acetic acid ethyl ester (46) BuildingBlock H Used

LCMS purity 97%, m/z 510 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.19 (3H,t, CH₃), 1.32-1.48 (4H, m, 2×CH₂), 1.54-1.73 (4H, m, 2×CH₂), 2.02-2.15(2H, m, CH₂), 2.50-2.70 (2H, m, CH₂), 3.10-3.30 (2H, m, CH₂), 4.10 (2H,m, CH₂), 4.70 (2H, m), 4.95 (1H, m), 5.35 (1H, s, OCOCHPh), 7.10-7.40(9H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-3-phenyl-propionicacid ethyl ester (47) Building Block H Used

LCMS purity 100%, m/z 524 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20 (3H,m, CH₃), 1.30-1.49 (4H, m, 2×CH₂), 1.55-1.70 (4H, m, CH₂), 2.10 (2H, m,CH₂), 2.60 (2 H, m), 2.88-3.25 (4H, m), 4.08-4.20 (2H, m, CH₂),4.45-4.62 (2H, m), 4.75 (1H, m), 5.03 (1H, m), 7.09-7.32 (9H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-3-phenyl-propionicacid (48) Building Block H Used

LCMS purity 100%, m/z 564 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.25-1.85(16H, m, 8×CH₂), 2.10 (2H, m, CH₂), 2.55 (2H, t, CH₂), 2.85-3.20 (4H,m), 4.40-4.60 (2H, m), 4.75 (1H, m), 4.95-5.15 (2H, m), 7.05-7.30 (9H,m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-3-phenyl-propionicacid (49) Building Block H Used

LCMS purity 100%, m/z 496 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.10-1.31(4H, m, 2×CH₂), 1.40-1.55 (4H, m, 2×CH₂), 1.98 (2H, m, CH₂), 2.43 (2H,m, CH₂), 2.75-3.10 (4H, m), 4.30-4.75 (3H, m), 4.90 (1H, m), 6.90-7.15(9H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-4-methyl-pentanoicacid ethyl ester (50) Building Block H Used

LCMS purity 98%, m/z 490 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 0.60 (1H,m, CH), 0.70-0.85 (6H, m, 2×CH₃), 1.25 (3H, t, CH₂CH₃ ), 1.38-1.65 (10H,m, 5×CH₂), 2.10 (2H, m, CH₂), 2.60 (2H, m, CH₂), 3.20 (2H, m, CH₂), 4.10(2H, q, CH₂ CH₃), 4.35 (1 H, m, CH), 4.70-4.80 (2H, m, CH₂), 4.95 (1H,m, CH), 7.23-7.25 (4H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-4-methyl-pentanoicacid cyclopentyl ester (51) Building Block H Used

LCMS purity 96%, m/z 530 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 0.75 (3H,d, CH₃), 0.88 (3H, d, CH₃), 1.30-1.90 (19H, m), 2.10 (2H, t, CH₂), 2.60(2H, m, CH₂), 3.15-3.30 (2H, m, CH₂), 4.30 (1H, m), 4.65-4.85 (2H, m),4.95 (1H, m), 5.10 (1H, m), 7.15-7.28 (4H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-4-methyl-pentanoicacid ethyl ester (52) Building Block H Used

LCMS purity 100%, m/z 462 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 0.60 (1H,m, CH), 0.70-0.85 (6H, m, 2×CH₃), 1.38-1.65 (10H, m, 5×CH₂), 2.10 (2H,m, CH₂), 2.40-2.60 (2H, m, CH₂), 3.20 (2H, m, CH₂), 4.35 (1H, m, CH),4.70-4.80 (2H, m, CH₂), 4.95 (1H, m, CH, masked signal), 7.23-7.25 (4H,m, Ar).

(S)-{[1-(7-Hydroxycarbamoyl-heptanoyl)-pyrrolidine-2-carbonyl]-amino}-phenyl-aceticacid cyclopentyl ester (53) Building Block I Used

LCMS purity 100%, m/z 488 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.30-2.45(24H, m), 3.50-3.70 (2H, m, CH₂), 4.55 (1H, m, CH), 5.18 (1H, m, CH),5.40 (1H, m, CH), 7.40 (5H, m, Ar).

(S)-{[1-(7-Hydroxycarbamoyl-heptanoyl)-pyrrolidine-2-carbonyl]-amino}-phenyl-aceticacid (54) Building Block I Used

LCMS purity 90%, m/z 420 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20-1.20(4H, m, 2×CH₂), 1.45-1.56 (4H, m, CH₂), 1.75-2.35 (8H, m), 3.35-3.60(2H, m), 4.45 (1H, m), 5.35 (1H, m), 7.18-7.35 (5H, m, Ar).

(S)-2-{[1-(7-Hydroxycarbamoyl-heptanoyl)-pyrrolidine-2-carbonyl]-amino}-3-phenyl-propionicacid ethyl ester (55) Building Block I Used

LCMS purity 100%, m/z 462 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20-2.20(19H, m), 2.94-3.20 (2H, m, CH₂ Ph), 3.48-3.69 (2H, m, CH₂ N), 4.10-4.25(2H, m, CH₂ CH₃), 4.33-4.49 (1H, m), 4.60-4.79 (1H, m), 7.20-7.35 (5H,m, Ar).

(S)-2-{[1-(7-Hydroxycarbamoyl-heptanoyl)-pyrrolidine-2-carbonyl]-amino}-3-phenyl-propionicacid cyclopentyl ester (56) Building Block I Used

LCMS purity 100%, m/z 502 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.27-2.23(22H, m, 11×CH₂), 2.35 (2H, m, CH₂), 2.97-3.27 (2H, m, CH₂ Ph),3.53-3.63 (2H, m, CH₂), 4.35-4.45 (1H, m, CH), 4.60-4.70 (1H, m,CHCH₂Ph), 5.10-5.20 (1H, m, CHOCO), 7.23-7.30 (5H, m, Ar).

(S)-2-{[1-(7-Hydroxycarbamoyl-heptanoyl)-pyrrolidine-2-carbonyl]-amino}-3-phenyl-propionicacid (57) Building Block I Used

LCMS purity 90%, m/z 434 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.30-1.41(4H, m, 2×CH₂), 1.55-1.69 (4H, m, 2×CH₂), 1.80-1.90 (8H, m), 2.91-3.26(2H, m), 3.45-3.70 (2H, m), 4.40 (1H, m), 4.72 (1H, m), 7.16-7.30 (5H,m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-4-carbonyl]-amino}-3-phenyl-propionicacid cyclopentyl ester (58) Building Block J Used

LCMS purity of 100%, m/z 563 [M⁺+H]⁺, ¹H NMR (400 MHz MeOD), δ:1.10-1.30 (3H, m, CH₃), 1.35-1.80 (8H, m, 4×CH₂), 2.15 (2H, m, CH₂),2.4-2.65 (2H, m, CH₂), 2.95-3.20 (3H, m), 4.0-4.2 (2H, m CH₂ O), 4.3-5.0(4H, m masked signal), 5.05-5.20 (1H, m CHOCO), 6.90-7.50 (9H, m, Ar).

(S)-2-{[(S)-2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-4-carbonyl]-amino}-3-phenyl-propionic acid (59) BuildingBlock J Used

LCMS purity of 100%, m/z 535 [M⁺+H]⁺, ¹H NMR (400 MHz MeOD), δ:1.20-1.40 (4H, m, 2×CH₂), 1.45-1.65 (4H, m, 2×CH₂), 1.90-2.10 (2H, m,CH₂), 2.30-2.50 (2H, m, CH₂), 2.70-3.15 (3H, m), 4.2-4.9 (4H, m maskedsignal), 5.00 (1H, m CHOCO), 6.75-7.40 (9H, m, Ar)

(S)-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-phenyl-aceticacid cyclopentyl ester (60) Building Block K Used

LCMS purity 100%, m/z 510 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.28 (4H,m, 2×CH₂), 1.40-1.80 (12H, m, 6×CH₂), 1.98 (2H, t, CH₂), 2.27 (2H, t,CH₂), 5.12 (1H, m), 5.50 (1H, s, OCOCHPh), 7.21-7.32 (4H, m, Ar), 7.36(2H, m, Ar), 7.45 (1H, d, Ar), 7.61 (1H, d, Ar), 7.90 (1H, s, Ar).

(S)-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-phenyl-aceticacid (61) Building Block K Used

LCMS purity 100%, m/z 442[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.21-1.34(4H, m, 2×CH₂), 1.48-1.63 (4H, m, 2×CH₂), 1.98 (2H, t, CH₂), 2.26 (2H,t, CH₂), 5.55 (1H, s, OCOCHPh), 7.20-7.32 (4H, m, Ar), 7.40 (2H, d, Ar),7.48 (1H, d, Ar), 7.64 (1H, d, Ar), 7.89 (1H, s, Ar).

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-4-methyl-pentanoicacid cyclopentyl ester (62) Building Block K Used

LCMS purity 93%, m/z 490 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 0.84 (3H,d, CH(CH₃ )), 0.88 (3H, d, CH(CH₃ )), 1.20-1.40 (4H, m, 2×CH₂),1.40-1.85 (15H, m, 6×CH₂, CH(CH₃)₂, CH₂ CH(CH₃)₂), 2.00 (2H, t, CH₂),2.25 (2H, t, CH₂), 4.45 (1H, m, OCOCHCH₂), 5.10 (1H, m, CHOCO), 7.25(1H, m Ar), 7.40 (1H, d, Ar), 7.60 (1H, d, Ar), 7.90 (1H, s, Ar).

(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-4-methyl-pentanoicacid (63) Building Block K Used

LCMS purity 97%, m/z 422 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.03 (3H,d, CH(CH₃ )), 1.06 (3H, d, CH(CH₃ )), 1.40-1.55 (4H, m, 2×CH₂),1.65-1.95 (7H, m, 2×CH₂, CH(CH₃)₂, CH₂ CH(CH₃)₂), 2.15 (2H, t, CH₂),2.45 (2H, t, CH₂), 4.70 (1H, m, OCOCHCH₂), 7.45 (1H, m, Ar), 7.60 (1H,d, Ar), 7.80 (1H, d, Ar), 8.05 (1H, s, Ar).

(S)-2-{[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-3-phenyl-propionicacid cyclopentyl ester(64) Building Block L Used

LCMS purity 100%, m/z 603 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.18-1.71(16H, m, 8×CH₂), 2.00 (2H, t, CH₂), 2.45 (2H, m), 2.70 (2H, m),2.90-3.11 (2H, m), 3.40 (1H, m), 4.10 (1H, m), 4.50 (1H, m), 5.00 (1H,m), 5.95 (1H, m), 6.90-7.11 (7H, m, Ar), 7.25 (1H, d, Ar), 7.34 (1H, d,Ar).

(S)-2-{[2-(7-Hydroxycarbamoyl-heptanoyl)-2,3,4,9-tetrahydro-1H-beta-carboline-1-carbonyl]-amino}-3-phenyl-propionicacid (65) Building Block L Used

LCMS purity 91%, m/z 535 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD δ: 1.15-1.32(4H, m, 2×CH₂), 1.40-1.60 (4H, m, 2×CH₂), 1.98 (2H, t, CH₂), 2.41 (2H,m), 2.69 (2H, m), 2.90-3.11 (2H, m), 3.30 (1H, m), 4.06 (1H, m), 4.60(1H, m), 5.92 (1H, m), 6.84 (7 H, m, Ar), 7.20 (1H, d, Ar), 7.31 (1H, d,Ar).

Synthesis of Compound (66) and Compound (67)

Stage 1: 5-Amino-nicotinic acid methyl ester

5-Aminonicotinic acid (1 g, 7.2 mmol) was suspended in methanol (100 ml)and thionyl chloride (4.22 ml, 57.9 mmol) added dropwise at 0° C. Thereaction mixture was stirred at room temperature for 18 h. The reactionmixture was evaporated to dryness and the resultant yellow oil wasre-dissolved in methanol/ether (1:1) and afforded yellow crystals (HClsalt) which were collected by filtration, yield 1.2 g (85%). LCMS purity91%, m/z 153 [M⁺+H]⁺,

Stage 2: (5-Amino-pyridin-3-yl)-methanol

5-Amino-nicotinic acid methyl ester (5.7 g, 30.2 mmol) was dissolved inTHF (150 ml) and LiAlH₄ (1M in THF solution 133 ml, 133 mmol) addedslowly at 0° C. The reaction mixture was stirred at room temperature for21 h. The reaction mixture was quenched and acidified to pH 3 usingdilute HCl, and basified (pH 8) using solid Na₂CO₃. Solvents wereremoved under reduced pressure. The residue was filtered through silicagel using 20% MeOH/DCM yielding the product 3.8 g, (100%) with LCMSpurity 97%, m/z 125 [M⁺+H]⁺, by ELS.

Stage 3: Coupling of stage 2 acid onto resin

Hydroxylamine-2-chlorotrityl resin derivatized with suberic acid (0.49g, 0.86 mmol/g, 0.42 mmol) was swollen in anhydrous DCM (6 ml) and PyBOP(0.67 g, 1.3 mmol) added. Stage 2 aniline (0.16 g, 1.3 mmol) was addedin DMF (6 ml) followed by DIPEA (0.75 ml, 4.2 mmol). LCMS following testcleavage indicated 27% conversion, m/z 296 [M⁺+H]⁺. The resin wasfiltered and washed using the standard wash procedure. The resin wasdried under vacuum.

Stage 4: Mesylation

Resin bound stage 3 alcohol (1.8 g, 1.57 mmol) was swollen in anhydrousDCM (30 ml) and DIPEA (1.62 ml, 9.42 mmol) was added at 0° C. followedby mesyl chloride (0.23 ml, 3.14 mmol). The reaction mixture was shakenat 0° C. for 30 minutes. LCMS following test cleavage indicated 21%conversion, m/z 374 [M⁺+H]⁺ and 9% by-product derived from chloridedisplacement of mesylate m/z 314 [M⁺+H]⁺. The resin was filtered andwashed using the standard wash procedure. The resin was dried undervacuum.

Stage 5: Displacement of mesylate with L-phenylalanine ethyl ester

Resin bound stage 4 product (0.5 g, 0.43 mmol) was swollen in anhydrousDMF (4 ml) and sodium iodide (0.05 g, 10% w/v) added. L-Phenylalanineethyl ester hydrochloride salt (0.3 g, 1.29 mmol) in anhydrous DMF (4ml) was added followed by DIPEA (0.75 ml, 4.3 mmol). After shaking for 3hours LCMS of test cleaved material indicated 35% conversion, m/z 471[M⁺+H]⁺. The resin was filtered and washed using the standard washprocedure. The resin was dried under vacuum.

Stage 6:(S)-2-{[5-(7-Hydroxycarbamoyl-heptanoylamino)-pyridin-3-ylmethyl]-amino}-3-phenyl-propionic acid ethyl ester (66)

Stage 5 resin (2 g, loading 0.87 mmol) was gently shaken in 2% TFA/DCM(20 ml) for 20 mins. The resin was filtered. The filtrate was collectedand evaporated under reduced pressure at room temperature. The resin wasre-treated with 2% TFA/DCM (20 ml) and filtered after 10 mins. Thecombined filtrates were evaporated to dryness under reduced pressure atroom temperature to give a crude product. The crude was purified bypreparative HPLC to yield compound (66) as the TFA salt. LCMS purity100%, m/z 471 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.10 (3H, t, CO₂CH₂CH₃), 1.31-1.50 (4H, m, 2×CH₂), 1.58-1.80 (4H, m, 2×CH₂), 2.05-2.15 (1H,m, CH), 2.24-2.38 (1H, m, CH), 2.45 (2H, t, CH₂), 3.10-3.20 (1H, m, CH),3.38-3.49 (1H, m, CH), 4.12 (2H, q, CH₂), 4.35 (3H, m, CH₂, CH)7.20-7.40 (5H, m, Ar), 8.30-9.00 (3H, m, Ar).

Stage 7:(S)-2-{[5-(7-Hydroxycarbamoyl-heptanoylamino)-pyridin-3-ylmethyl]-amino}-3-phenyl-propionic acid (67)

To a solution of Stage 6 product (30 mg, loading 1.8 mmol/g) in THF (1ml) was added 1.4M sodium hydroxide (1 ml). The reaction mixture wasstirred for 30 minutes. LCMS showed 75% conversion, m/z 442[M⁺+H]⁺. Thereaction mixture was evaporated to dryness and was purified bypreparative HPLC to yield the desired compound as the TFA salt, compound(67). LCMS purity 100%, m/z 443 [M⁺+H]⁺. ¹H NMR (400 MHz, MeOD), δ: 1.30(4H, m, 2×CH₂), 1.50-1.70 (4H, m, 2×CH₂), 2.00 (2H, t, CH₂), 2.30 (2H,t, CH₂), 3.20 (2H, m, CH₂ Ph, masked signal), 4.20 (3H, m), 7.20 (5H, m,Ar), 8.30 (1H, br s, Ar), 8.40 (1H, s, Ar), 8.65 (1H, br s, Ar).

Synthesis of Compound (68)

(S)-2-{[5-(7-Hydroxycarbamoyl-heptanoylamino)-pyridin-3-ylmethyl]-amino}-3-phenyl-propionicacid tert-butyl ester (68) (was prepared using the procedure outlinedfor the preparation of compound (66): LCMS purity 100%, m/z 499 [M⁺+H]⁺,¹H NMR (400 MHz, MeOD), δ: 1.20 (9H, s, C(CH ₃)₃), 1.25-1.35 (4H, m,2×CH₂), 1.49-1.65 (4H, m, 2×CH₂), 2.00 (2H, t, CH₂), 2.35 (3H, t, CH₂),3.00 (1H, m), 3.32 (1H, m), 4.15-4.30 (3H, m), 7.15-7.30 (5H, m, Ar),8.30 (1H, br s, Ar), 8.45 (1H, s, Ar), 8.65 (1H, br s, Ar).

Synthesis of Compound (69) and Compound (70)

Stage 1: Loading of Fmoc Amino Caproic Acid onto Resin

To a mixture of hydroxylamine 2-chlorotrityl resin (2.5 g, loading 0.94mmol/g) in anhydrous DCM (10 ml) was added a solution of1,3-diisopropylcarbodiimide (1.1 ml, 7.05 mmol) and 6-(Fmoc-amino)caproic acid (2.5 g, 7.05 mmol) in anhydrous DCM (10 ml). DMF (5 ml) wasadded and the reaction shaken at room temperature for 1 h. Test cleavagerevealed 96% conversion to required product. The resin was filtered andwashed using the standard wash procedure. The resin was dried undervacuum.

Stage 2: Fmoc Deprotection

Stage 1 Fmoc protected amine resin (2.0 g, loading 0.94 mmol/g) wasdissolved in a solution of 20% piperidine in DMF (25 ml, excess) andshaken at room temperature for 30 minutes. A test cleavage indicatedcomplete conversion by LCMS, 100% (ELS detection). The resin wasfiltered, washed using the standard wash procedure and dried undervacuum.

Stage 3: Coupling Reaction

To resin bound stage 2 amine (2.0 g, loading 0.94 mmol/g) in anhydrousDCM (10 ml) and DMF (10 ml) was added DIC (0.71 ml, 5.64 mmol) and3-(chloromethyl)benzoic acid (0.96 g, 5.64 mmol). The mixture was shakenfor 1 hour before test cleavage revealed 49% conversion by LCMS, m/z 219[M⁺+H]⁺. The resin was filtered and washed using the standard washprocedure. The resin was dried under vacuum.

Stage 4: Chloride Displacement with L-Phenylglycine Cyclopentyl Ester

To resin bound stage 3 chloride (0.5 g, 0.47 mmol) in anhydrous DMF (5ml) was added L-phenylglycine cyclopentyl ester tosyl salt (0.57 g, 1.41mmol), DIPEA (0.24 ml, 1.41 mmol) and a catalytic amount of sodiumiodide. The reaction mixture was heated at 60° C. for 1 hour. LCMSfollowing test cleavage revealed 45% conversion, m/z 482 [M⁺+H]⁺. Theresin was filtered and washed using the standard wash procedure. Theresin was dried under vacuum.

Stage 5:(S)-[3-(5-Hydroxycarbamoyl-pentylcarbamoyl)-benzylamino]-phenyl-aceticacid cyclopentyl ester (69)

Stage 4 resin (1.0 g, loading 0.94 mmol/g) was gently shaken in 2%TFA/DCM (10 ml) for 20 mins. The resin was filtered. The filtrate wascollected and evaporated under reduced pressure at room temperature. Theresin was re-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered.The combined filtrates were evaporated to dryness under reduced pressureat room temperature to give a residue. The residue was purified bypreparative HPLC to yield compound (69). LCMS purity 89%, m/z 482[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.24-1.82 (14H, m, 7×CH₂), 2.03 (2H,t, CH₂), 3.30 (2H, t, CH₂), 4.08 (1H, d, CHHPh), 2.20 (1H, d, CHHPh),5.09 (1H, s, OCOCHPh), 5.18 (1H, m, CHOCO), 7.39-7.54 (7H, m, Ar), 7.77(2H, m, Ar).

Stage 6: Saponification of Cyclopentyl Ester

Stage 4 resin (1.35 g, loading 0.94 mmol/g) was suspended in THF (4.7ml) and methanol (4.7 ml). 1.4M sodium hydroxide was added (9.4 ml,12.66 mmol). The mixture was shaken for 48 h. LCMS of the test cleaveshowed 49% conversion to the acid, m/z 414 [M⁺+H]⁺. The resin wasfiltered and washed with water×2, MeOH×2, followed by the standard washprocedure. The resin was dried under vacuum

Stage 7:(S)-[3-(5-Hydroxycarbamoyl-pentylcarbamoyl)-benzylamino]-phenyl-aceticacid (70)

Stage 6 resin (1.35 g, loading 0.94 mmol/g) was gently shaken in 2%TFA/DCM (10 ml) for 20 mins. The resin was filtered. The filtrate wascollected and evaporated under reduced pressure at room temperature. Theresin was re-treated with 2% TFA/DCM (10 ml) and after 20 mins filtered.The combined filtrates were evaporated to dryness under reduced pressureat room temperature to give a residue. The residue was purified bypreparative HPLC to yield compound (70). LCMS purity 100%, m/z 414[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.30 (2H, m, CH₂), 1.57 (4H, m,2×CH₂), 2.20 (2H, t, CH₂), 3.30 (2H, t, CH₂), 4.05 (1H, d, CHHPh), 4.18(1H, d, CHHPh), 4.90 (1H, s, OCOCHPh), 7.35-7.52 (7H, m, Ar), 7.78 (2H,m, Ar).

Synthesis of Compounds in FIG. 4 Exemplified by Compound (71) andCompound (72)

Preparation of Building Blocks M,N,O Building Block M

Stage 1: 2-(3-Amino-phenyl)-ethanol

A mixture of nitro phenethyl alcohol (8.0 g, 0.047 mol) and 10% Pd/C(0.6 g) in ethanol (100 ml) was stirred under a hydrogen atmosphere(balloon pressure) for 18 h. The reaction mixture was filtered through apad of celite and the Pd/C catalyst removed. The filtrate wasconcentrated under reduced pressure to yield a light brown solid 6.1 g(95% yield). LCMS purity 98%, m/z 138 [M+H]⁺.

Stage 2: 3-(2-Bromo-ethyl)-phenylamine

A solution of 2-(3-Amino-phenyl)-ethanol (2.0 g) in 48% aq HBr (20 ml)was heated at 90° C. for 18 h. The mixture was cooled to roomtemperature, and the precipitate formed was collected by filtration. Thesolid was dried in vacuo yielding Building block M, 1.8 g (61% yield).LCMS purity 90%, m/z 200/202 [M+H]⁺.

Building Block N

Stage 1: 2-(3-Nitro-phenoxy)-ethanol

To a solution of 3-nitrophenol (10 g, 71.9 mmol) in DMF (40 ml) wasadded NaOH pellets (3.16 g, 79.1 mmol) and 2-bromoethanol (5.6 ml, 79.1mmol). The reaction mixture was heated at 60° C. for 18 h. LCMSindicated 65% conversion to the required product. The reaction mixturewas diluted with water (10 ml) and was slowly neutralised with 2M HCl.The reaction mixture was extracted with EtOAc (50 ml) and washed withwater (50 ml). The EtOAc layer dried (Na₂SO₄), filtered and evaporatedto dryness. Flash column chromatography purification eluting with 30%EtOAc/heptane gave the required product (8.2 g, 62% yield). LCMS purity100%, m/z 184 [M+H]⁺.

Stage 2: 2-(3-Amino-phenoxy)-ethanol

Reduction was carried out using the procedure outlined for Buildingblock M.

Stage 3: 3-(2-Bromo-ethoxy)-phenylamine

Bromination was carried out using the procedure described for Buildingblock M.

Building Block O

Building block O was prepared as described for Building block G with3-bromo-1-propanol used in place of 2-bromoethanol.

Synthesis of Compounds in FIG. 4 Exemplified for Compound (71, Rcyclopentyl) and Compound (72, R═H)

Stage 1: Coupling of Aniline Derivative to Carboxylic AcidFunctionalised Resin

To a suspension of hydroxylamine 2-chlorotrityl resin derivatized withsuberic acid (1.0 g, 0.94 mmol, loading 0.94 mmol) in DCMIDMF (10ml/iOml) was added DIPEA (1.75 ml) followed by building block M, 0.8 g,2.82 mmol. PyBrOP (0.53 g, 3.76 mmol) was added and the suspensionshaken for 18 h. The resin was washed using the standard wash procedureand was thoroughly dried.

Stage 2: Displacement of Bromide with L-phenylglycine Cyclopentyl Ester

To a suspension of stage 1 resin (0.4 g, 0.38 mmol) in DMF (4 ml) in avial, was added L-phenylglycine cyclopentyl ester tosyl salt (0.44 g,1.12 mmol) and DIPEA (0.67 ml, 3.76 mmol) followed by NaI (50 mg). Thereaction was allowed to stand at 65° C. for 8 h. The resin wasthoroughly washed using the standard wash procedure.

Stage 3:(S)-{2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenyl]-ethylamino}-phenyl-aceticacid cyclopentyl ester (71)

Stage 2 resin was cleaved with 2% TFA/DCM (10 ml×3). The filtrate wasconcentrated to dryness and the residue purified by preparative HPLC toafford compound (71) as the TFA salt. Yield 21 mg (11% overall), LCMSpurity 99%, m/z 510 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.35-1.95 (16H,m 8×CH₂), 2.10 (2H, t, CH₂), 2.38 (2H, t, CH₂), 2.91-3.29 (4H, m), 5.18(1H, s, OCOCHPh), 5.32 (1H, m, CHOCO), 6.98 (1H, m, Ar), 7.30 (2H, m,Ar), 7.47-7.56 (5H, m, Ar), 7.62 (1H, s, Ar).

Stage 4: Saponification

Stage 2 resin (1.2 g, 1.12 mmol) was suspended in THF/MeOH (12 ml/12ml). 2.7M NaOH solution added and mixture was shaken for 18 h at roomtemperature Upon completion of reaction the resin was thoroughly washed(Standard wash procedure).

Stage 5:(S)-{2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenyl]-ethylamino}-phenyl-aceticacid (72)

Stage 4 resin (0.8 g, 0.76 mmol) was cleaved with 2% TFA/DCM (10 ml×3).Filtrate was concentrated to dryness and residue purified by preparativeHPLC to give compound (72) as a TFA salt, yield 40 mg (10% overall).LCMS purity of 100%, m/z 442 [M⁺+H]⁺, ¹H NMR (400 MHz MeOD), δ:1.20-1.35 (4H, m, 2×CH₂),1.45-1.70 (4 H, m, 2×CH₂), 1.95 (2H, t, CH₂),2.25 (2H, t, CH₂), 2.80-3.20 (4H, m CHaNH, C1H₂Ph), 5.00 (1H, s,CHCOOH), 6.85 (1H, m, Ar), 7.15 (2H, m, Ar), 7.40 (5H, s, Ar), 7.50 (1H,s, Ar).

The following compounds were prepared according to the proceduredescribed for compounds (71) and compound (72)

(S)-2-[(2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-ethylamino]-3-phenyl-propionicacid cyclopentyl ester (73) Building Block N Used

LCMS purity 94%, m/z 540 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.26-1.82(16H, m, 8×CH₂), 2.11 (2H, t, CH₂), 2.39 (2H, t, CH₂), 3.15 (1H, dd,CHHPh), 3.44 (1H, dd, CHHPh), 3.56 (2H, m, CH₂), 4.30 (2H, t, CH₂), 4.40(1H, m), 5.13 (1H, m, CHOCO), 6.76 (1H, d, Ar), 7.00 (1H, d, Ar),7.24-7.41 (6H, m, Ar), 7.57 (1H, s, Ar).

(S)-2-[(2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-ethylamino]-3-phenyl-propionicacid (74) Building Block N Used

LCMS purity 100%, m/z 472 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.35-1.46(4H, m, 2×CH₂), 1.61-1.77 (4H, m, 2×CH₂), 2.11 (2H, t, CH₂), 2.40 (2H,t, CH₂), 3.28-3.40 (2H, m, CH₂, masked signal), 3.53 (2H, t, CH₂), 4.29(2H, t, CH₂), 4.38 (1H, t, OCOCHCH₂), 6.75 (1H, d, Ar), 7.00 (1H, d,Ar), 7.25 (1H, t, Ar), 7.30-7.41 (5H, m, Ar), 7.53 (1H, s, Ar).

(S)-2-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-propylamino}-3-phenyl-propionicacid cyclopentyl ester (75) Building Block O Used

LCMS purity 100%, m/z 554 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.29-1.87(16H, m, 8×CH₂), 2.10 (2H, t, CH₂), 2.21 (2H, m, CH₂), 2.37 (2H, t,CH₂), 3.12 (1H, dd, CHHPh), 3.25-3.43 (3H, m, CHHPh, CH₂), 4.11 (2H, t,CH₂), 4.33 (1H, m, OCOCHCH₂), 5.18 (1H, m, CHOCO), 6.78 (1H, d, Ar),7.00 (1H, d, Ar), 7.22 (1H, t, Ar), 7.24-7.39 (5H, m, Ar), 7.44 (1H, s,Ar).

(S)-2-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-propylamino}-3-phenyl-propionicacid (76) Building Block O Used

LCMS purity 100%, m/z 486 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.34-1.47(4H, m, 2×CH₂), 1.60-1.75 (4H, m, 2×CH₂), 2.10 (2H, t, CH₂), 2.19 (2H,m, CH₂), 2.38 (2H, t, CH₂), 3.25-3.40 (4H, m, 2×CH₂, masked signal),4.09 (2H, t, CH₂), 4.35 (1H, OCOCHCH₂), 6.75 (1H, d, Ar), 6.98 (1H, d,Ar), 7.20 (1H, t, Ar), 7.28-7.39 (5H, m, Ar), 7.41 (1H, s, Ar).

(S)-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-propylamino}-phenyl-acetic acid cyclopentyl ester (77) Building Block O Used

LCMS purity of 100%, m/z 540 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ:1.20-1.50 (8H, m, 4×CH₂), 1.50-1.80 (8H, m, 4×CH₂), 1.80-1.90 (2H, m,NHCH₂CH₂ ), 2.00 (2H, t, CH₂), 2.25 (2H, t, CH₂), 2.55-2.70 (2H, m,NHCH₂ ), 3.90 (2H, t, CH₂CH₂ O), 4.25 (1H, s, OCOCHPh), 5.05 (1H, m,CHOCO), 6.55 (1H, m, Ar), 6.95 (1H, m, Ar), 7.00-7.10 (1H, m, Ar),6.15-6.35 (6H, m, Ar)

(S)-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-propylamino}-phenyl-aceticacid cyclopentyl ester (78) Building Block O Used

LCMS purity of 100%, m/z 472 [M⁺+H]⁺, ¹H NMR (400 MHz, DMSO), δ:1.20-1.40 (4H, m, 2×CH₂), 1.45-1.65 (4H, m, 2×CH₂), 1.90 (2H, m,NHCH₂CH₂ ), 2.00-2.20 (2H, m, CH₂), 2.20-2.35 (2H, m, CH₂), 2.80-3.10(2H, m, NHCLH₂ masked signal), 3.90-4.00 (2H, m, CH₂CH₂ O), 4.60-4.85(1H, br s, OCOCHPh), 6.55 (1H, d, Ar), 7.05 (1 H, d, Ar), 7.15 (1H, m,Ar), 7.30-7.60 (6H, m, Ar), 8.50-8.85 (1H, brs), 9.85 (1H, s), 10.35(1H, s).

Synthesis of Compounds in FIG. 5 Exemplified by Compound 79 and Compound80

Synthesis of Compound 79 (R=cyclopentyl) and Compound 80 (R═H)

Stage 1: 3-Nitro-benzylamine

3-Nitrobenzyl bromide (10 g, 46.3 mmol) was dissolved in ethanol (200ml) and stirred at room temperature A solution of conc. NH₃ (aq) (200ml) in ethanol (300 ml) was added dropwise to the reaction over 30minutes. The reaction was stirred for 18 h at room temperature beforeevaporating to dryness. Water (350 ml) was added to the residue and thesolution was washed with EtOAc (2×200 ml). The aqueous layer wasbasified with 1 M NaOH and extracted with EtOAc (2×200 ml). The organicextracts of the basic layer were combined, dried (Na₂SO₄) and evaporatedto dryness. The product was obtained as an orange oil (4.6 g, 65%yield). LCMS purity 100%, m/z 153 [M⁺+H]⁺.

Stage 2: 1-Isocyanatomethyl-3-nitro-benzene

3-Nitro-benzylamine (2.3 g, 15.1 mmol) was dissolved in anhydrousdioxane (50 ml) under N₂ atmosphere. Diphosgene (2.2 ml, 18.2 mmol) wasadded, a precipitate formed which dissolved upon heating to 75° C. Thereaction was stirred at 75° C. for 3 h, cooled and evaporated to drynessgiving 3.4 g of crude material which was used in the next step withoutfurther purification.

Stage 3: (S)-[3-(3-Nitro-benzyl)-ureido]-phenyl-acetic acid cyclopentylester

L-phenylglycine cyclopentyl ester tosyl salt (7.47 g, 19.1 mmol) wasdissolved in DMF (70 ml). Triethylamine (5.8 ml, 42.0 mmol) was addedand the mixture was cooled to 0° C. A solution of1-Isocyanatomethyl-3-nitro-benzene (3.4 g, 19.1 mmol in 30 ml of DMF)was added slowly to the reaction mixture under a N₂ atmosphere. Stirringwas continued for 18 h allowing the reaction to warm to room temperatureThe mixture was diluted with water (200 ml) and extracted with EtOAc(2×200 ml). The organic extracts were washed with water (3×100 ml) andbrine (100 ml), dried (Na₂SO₄) and evaporated to dryness. The crude ureawas purified by column chromatography (1% MeOH/DCM) to yield a paleyellow oil (4.6 g, 65% yield). LCMS purity 85%, m/z 398 [M⁺+H]⁺.

Stage 4: (S)-[3-(3-Amino-benzyl)-ureido]-phenyl-acetic acid cyclopentylester

(S)-[3-(3-Nitro-benzyl)-ureido]-phenyl-acetic acid cyclopentyl ester(3.6 g, 9.0 mmol) was dissolved in ethanol (50 ml) Pd/C (10% wet)catalyst (100 mg) was added and the mixture was stirred under H₂atmosphere (balloon pressure) for 18 h. The reaction mixture wasfiltered through a celite plug and evaporated to dryness to give apurple oil (2.34 g, 71% yield). LCMS purity 90%, m/z 368 [M⁺+H]⁺.

Stage 5: Coupling to Resin

Hydroxylamine 2-chlorotrityl resin derivatized with suberic acid (1.5 g,loading 0.94 mmol/g) was swollen in DMF (15 ml) and PyBOP (2.2 g, 4.23mmol) added, followed by DIPEA (2.4 ml, 14.1 mmol). Stage 4 aniline (1.3g, 3.53 mmol) was dissolved in DCM (15 ml) and added to the reactionmixture. The reaction was shaken for 42 h at room temp before standardresin wash and drying.

Stage 6:(S)-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzyl]-ureido}-phenyl-aceticacid cyclopentyl ester (79)

Stage 5 resin bound cyclopentyl ester (1.75 g) was shaken with 2%TFA/DCM (15 ml) for 10 min before filtering the resin and evaporatingthe solvent under reduced pressure at room temperature This process wasrepeated (X³) and the combined crude product was purified by preparativeHPLC to yield compound (79). LCMS purity 100%, m/z 539 [M⁺+H]⁺, ¹H NMR(400 MHz, MeOD), δ: 1.34-1.90 (16H, m, 8×CH₂), 2.11 (2H, t, CH₂), 2.38(2H, t, CH₂), 4.30 (2H, s, CH₂), 5.18 (1H, m, CHOCO), 5.30 (1H, s,OCOCHPh), 7.05 (1H, d, Ar), 7.26 (1H, t, Ar), 7.34-7.40 (5H, m, Ar),7.47 (2 H, m, Ar).

Stage 7:(S)-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzyl]-ureido}-phenyl-aceticacid (80)

Compound (79) (75 mg) was dissolved in THF (1 ml) and 2M NaOH (aq, 1 ml)added. The reaction was stirred at room temperature for 2 h. THF wasremoved under a stream of N₂ and the aqueous layer (˜1 ml) was purifiedby preparative HPLC to yield compound (80). LCMS purity 99%, m/z 471[M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20-1.35 (4H, m, 2×CH₂), 1.45-1.65(4H, m, 2×CH₂), 2.00 (2H, t, CH₂), 2.25 (2 H, t, CH₂), 4.20 (2H, s CH₂NH), 5.25 (1H, s CHPh), 6.90 (1H, d, Ar), 7.10 (1H, t, Ar), 7.15-7.40(7H, m, Ar).

The following compounds were prepared according to the proceduredescribed for compounds (79) and compound (80)

(S)-2-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzyl]-ureido}-3-phenyl-propionicacid cyclopentyl ester (81)

LCMS purity 95%, m/z 553 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.20-1.40(4H, m, 2×CH₂), 1.40-1.80 (12H, m, 6×CH₂), 2.00 (2H, t, CH₂), 2.25 (2H,t, CH₂), 2.90 (2 H, m, CHCH₂ Ph), 4.15 (2H, s CH₂ NH), 4.40 (1H, m,OCOCHCH₂), 5.00 (1H, m, CHOCO), 6.85 (1H, d, Ar), 7.00-7.25 (6H, m, Ar),7.35 (2H, br s, Ar).

(S)-2-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzyl]-ureido}-3-phenyl-propionicacid (82)

LCMS purity 94%, m/z 485 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.30-1.50(4H, m, 2×CH₂), 1.60-1.80 (4H, m, 2×CH₂), 2.10 (2H, t, CH₂), 2.35 (2H,t, CH₂), 2.95-3.25 (2H, m, CHCH₂ Ph), 4.25 (2H, s, CH₂ NH), 4.60 (1H , mOCOCHCH₂), 7.00 (1H, d, Ar), 7.15-7.35 (6H, m, Ar), 7.45 (2H, m, Ar)

Synthesis of Compounds Outlined in FIG. 6 Exemplified by Compound (83)and Compound (84)

Stage 1: 7-(1-Isobutoxy-ethoxycarbamoyl)-heptanoic acid methyl ester

Monomethyl suberate (25.0 g, 13.3 mmol, 1.0 eq) was dissolved in THF(300 mL) and DCM (300 mL). EDC.HCl (25.46 g, 13.3 mmol, 1.0 eq) wasadded to the stirred solution, followed by HOBt (17.95 g, 13.3 mmol, 1.0eq) and triethylamine (48.5 mL, 34.5 mmol, 2.6 eq).O-(1-Isobutoxy-ethyl)-hydroxylamine (21.9 mL, 15.9 mmol, 1.2 eq) wasadded to the viscous solution and the reaction allowed to stir overnightat room temperature. The reaction mixture was concentrated under vacuum,DCM (350 mL) was added and washed with water (250 mL) and brine (200mL). The organic layer was isolated, dried (MgSO₄), filtered andconcentrated in vacuo. The product was obtained as a white solid (36.6g, 91% yield) LCMS purity 88%, m/z 302 (M⁺+H)⁺. This was used in thenext step without further purification.

Stage 2: 7-(1-Isobutoxy-ethoxycarbamoyl)-heptanoic acid

7-(1-Isobutoxy-ethoxycarbamoyl)-heptanoic acid methyl ester (36.6 g,12.1 mmol, 1.0 eq) was stirred in THF (200 mL) and water (200 mL) in thepresence of lithium hydroxide (8.68 g, 36.2 mmol, 3.0 eq) for 3 h at 50°C. THF was evaporated under vacuum and to the mixture water (100 mL) andethyl acetate (200 mL) were added. The mixture was acidified cautiouslyto pH 3 by addition of 1 N HCl. The organic phase was isolated and theaqueous layer re-extracted with ethyl acetate (150 mL). The organicphases were combined, dried (MgSO₄), filtered and concentrated in vacuo.The product was obtained as a white solid (29.0 g, 83% yield), m/z 288[M⁺+H]⁺ and used in stage 4 without further purification.

Stage 3: 4-Trimethylsilanyloxymethyl-phenylamine

To a stirred solution of 4-amino benzyl alcohol (16.0 g, 13.0 mmol, 1.0eq) in THF (400 mL), was added triethylamine (18.9 mL, 13.6 mmol, 1.05eq) followed by trimethylchlorosilane (17.2 mL, 13.6 mmol, 1.05 eq). Thereaction mixture was stirred under a nitrogen atmosphere overnight atroom temperature. THF was evaporated under vacuum and the mixturepartitioned with ethyl acetate (300 mL) and water (300 mL). The organicphase was isolated and the aqueous layer re-extracted with ethyl acetate(2×100 mL). The combined organic phases were washed with brine (2×150mL), dried (MgSO₄), filtered and concentrated in vacuo. The product wasobtained as a yellow oil (24.0 g, 95% yield) and used in stage 4 withoutfurther purification.

Stage 4: Octanedioic acid (4-hydroxymethyl-phenyl)-amide(1-isobutoxyethoxy)-amide

7-(1-Isobutoxy-ethoxycarbamoyl)-heptanoic acid (5.0 g, 1.72 mmol, 1.0eq) and 4-trimethylsilanyloxymethyl-phenylamine (3.38 g, 1.72 mmol, 1.0eq) were stirred together in DMF (140 mL). To the mixture was addedPyBroP (10.5 g, 2.25 mmol, 1.3 eq) and DiPEA (3.9 mL, 2.25 mmol, 1.3eq). The reaction was stirred under a nitrogen atmosphere overnight atroom temperature. Ethyl acetate (200 mL) and water (200 mL) were added.The aqueous phase was isolated and re-extracted with ethyl acetate(2×100 mL). The combined organic phases were washed with water (2×50 mL)and brine (50 mL), then dried (MgSO₄), filtered and concentrated invacuo. The crude product was dissolved in the minimum of ethyl acetateand purified by passing through a pad of silica. The product was washedthrough the silica using ethyl acetate and collected in 100 mL conicalflasks until elution ceased by LCMS analysis. Purification gave a yellowoil (3.59 g, 53% yield). LCMS purity 61%, m/z 417 [M++Na]+

Stage 5: Octanedioic acid(4-formyl-phenyl)-amide(1-isobutoxy-ethoxy)-amide

Octanedioic acid (4-hydroxymethyl-phenyl)-amide(1-isobutoxyethoxy)-amide(100 mg, 0.025 mmol, 1.0 eq) was dissolved in DCM (5 mL). To thereaction mixture, was added MnO₂ (286 mg, 0.33 mmol, 13.0 eq) and wasstirred at room temperature for 1.5 h. The reaction mixture was filteredover Celite and washed through with DCM, followed by evaporation ofsolvent to give a yellow oil (78.6 mg, 79% yield) LCMS purity 53%, m/z415 [M++Na]⁺. The product was used in the subsequent steps withoutfurther purification.

Stage 6:(R)-{4-[7-(1-Isobutoxy-ethoxycarbamoyl)-heptanoylamino]-benzylamino}-phenyl-aceticacid cyclopentyl ester

Octanedioic acid (4-formyl-phenyl)-amide(1-isobutoxy-ethoxy)-amide (276mg, 0.70 mmol, 1.0 eq) and D-phenylglycine cyclopentyl ester (170 mg,0.77 mmol, 1.1 eq) were stirred in DCE (15 mL) for 10 min. Acetic acid(65 μL) was added and stirred for 2 min. Sodium triacetoxyborohydride(448 mg, 0.21 mmol, 3.0 eq) was introduced and the reaction mixturestirred under a nitrogen atmosphere, at room temperature for 1 h. Sodiumhydrogen carbonate was added to quench the reaction. DCM was then addedand the organic phase isolated. The aqueous layer was re-extracted withDCM, organic layers combined, dried (MgSO₄), filtered and concentratedin vacuo to give crude product (100 mg, 24%) LCMS purity 94.0%, m/z 496[m⁺+H]⁺ which was taken on without further purification.

Step 7:(R)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid cyclopentyl ester (83)

(R)-{4-[7-(1-Isobutoxy-ethoxycarbamoyl)-heptanoylamino]-benzylamino}-phenyl-aceticacid cyclopentyl ester (50 mg, 0.08 mmol, 1 eq) was dissolved in DCM(0.5 mL) and stirred with 4M HCl in dioxane (0.2 mL) for 30 min. Theresulting salt was concentrated, dissolved in methanol and purified bypreparative HPLC to yield compound (83). LCMS purity 94%, m/z 496[M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.41-1.95 (16H, m, 8×CH₂), 2.15-2.17(2H, m, CH₂), 2.40 (2H, t, J=7.2 Hz, CH₂), 4.16 (2H, q, J=13.5 Hz, CH₂),5.12 (1H, s, CH), 5.27-5.30 (1H, m, CH), 7.40 (2H, d, J=8.7 Hz, Ar—H),7.50-7.56 (5H, m, Ar—H), 7.67 (2H, d, J=8.7 Hz, Ar—H).

Stage 8:(R)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid (84)

To a solution of CHR-003644 (50 mg, 0.008 mmol, 1.0 eq) in THF (2 mL)and water (2 mL), was added LiOH (8.0 mg, 0.033 mmol, 4.0 eq). Thereaction was stirred under a nitrogen atmosphere at 40° C. overnight.THF was evaporated under vacuum and the remaining aqueous reactionsolvent washed with ethyl acetate. The solution was acidified to pH 3and the product concentrated in vacuo. The resulting salts weredissolved in methanol and the product purified by preparative HPLC toyield compound (84). LCMS purity 97%, m/z 428 [M⁺+H]⁺, ¹H NMR (300 MHz,MeOD), δ: 1.39-1.41 (4H, m, 2×CH₂), 1.62-1.74 (4H, m, 2×CH₂), 2.13-2.15(2H, m, CH₂), 2.40 (2H, t, J=7.5 Hz, CH₂), 4.14 (2H, q, J=12.9 Hz, CH₂),5.06 (1H, s, CH), 7.39 (2H, d, J=8.4 Hz, Ar—H), 7.54 (5H, s, Ar—H), 7.67(2H, d, J=8.7 Hz, Ar—H)

The following Compound was Prepared in a Similar Manner to Compound (83)and Compound (84) using the Appropriate Intermediates.

(S)-2-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-methyl-pentanoicacid cyclopentyl ester (85)

LCMS purity 97%, m/z 476 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 0.98-1.03(6H, m, 2×CH₃), 1.41-1.42 (4H, m, 2×CH₂), 1.71-1.96 (14H, m, 7×CH₂),2.10-2.15 (2H, m, CH₂), 2.40 (2H, t, J=7.2 Hz, CH₂), 3.96-4.01 (1H, m,CH), 4.15-4.26 (2H, m, CH₂), 4.81 (1H, s, CH), 5.31-5.34 (1H, m, CH),7.44 (2H, d, J=8.7 Hz, Ar—H), 7.70 (2H, d, J=8.7 Hz, Ar—H)

(S)-Cyclohexyl-[4-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-aceticacid (87)

LCMS purity 95%, m/z 434 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.23-1.96(18H, m, 9×CH₂), 2.10-2.15 (2H, m, CH₂), 2.39 (2H, m, CH₂), 3.71 (1H, m,CH), 4.12 (2H, q, J=7.2 Hz, CH₂), 4.80 (1H, s, CH), 7.43 (2H, d, J=8.4Hz, Ar—H), 7.68 (2H, d, J=8.7 Hz, Ar—H)

(S)-3-tert-Butoxy-2-[4-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-butyricacid cyclopentyl ester (88)

LCMS purity 83%, m/z 520 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.19 (9H,s, 3×CH₃), 1.29 (3H, d, J=7.8 Hz, CH₃), 1.37-1.41 (4H, m, CH₂),1.64-1.89 (12H, m, CH₂), 2.09-2.15 (2H, m, CH₂), 2.40 (2H, t, J=7.2 Hz,CH₂), 3.36-3.37 (1H, m, CH), 3.70-3.71 (1H, m, CH), 4.24-4.27 (2H, m,CH₂), 5.17-5.19 (1H, m, CH), 7.42 (2H, d, J=6.9 Hz, Ar—H), 7.68 (2H, d,J=8.4 Hz, Ar—H)

(S)-3-tert-Butoxy-2-[4-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-propionicacid cyclopentyl ester (89)

LCMS purity 95%, m/z 506 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.23 (9H,s, C(CH₃)₃), 1.36-2.09 (16H, m, 8×CH₂), 1.66 (2H, t, J=7.7 Hz, CH₂),1.75 (2H, t, J=7.4 Hz, CH₂), 2.11 (2H, t, J=7.4 Hz, CH₂), 2.40 (2H, t,J=7.3 Hz, CH₂), 3.92 (2H, m, CH₂), 4.16 (1H, m, CH), 4.26 (2H, s, CH₂),5.32 (1H, m, CH), 7.45 (2H, d, J=8.5 Hz, ArH), 7.67 (2H, dd, J=3.2, 8.3Hz, ArH).

(S)-3-tert-Butoxy-2-[4-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-propionicacid (90)

LCMS purity 95%, m/z 438 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.25 (9H,s, C(CH₃)₃), 1.39-1.42 (4H, m, 2×CH₂), 1.62-1.69 (4H, m, 2×CH₂),2.08-2.17 (2H, m, CH₂), 2.40 (2H, t, J=7.5 Hz, CH₂), 3.85-3.96 (2H, m,CH₂), 4.01-4.04 (1H, m, CH), 4.26 (2H, s, CH₂), 7.46 (2H, d, J=8.4 Hz,Ar—H), 7.68 (2H, d, J=8.4 Hz, Ar—H)

(S)-2-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-3-phenyl-propionicacid cyclopentyl ester (91)

LCMS purity 95%, m/z 510 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.17-2.43(22H, m, 11×CH₂), 4.19-4.30 (2H, m, CH₂), 5.08 (1H, s, CH), 5.20-5.26(1H, m, CH), 7.24-7.71 (9H, m, Ar—H)

Compound (86) was Prepared was Prepared Via Alternative Methodology theModified Conditions are Detailed Below

Step 6b:(S)-Cyclohexyl-{4-[7-(1-isobutoxy-ethoxycarbamoyl)-heptanoylamino]-benzylamino}-aceticacid cyclopentyl ester

Octanedioic acid (4-formyl-phenyl)-amide(1-isobutoxy-ethoxy)-amide (220mg, 0.056 mmol, 1.0 eq) and L-cyclohexyl-glycine cyclopentyl ester(138.9 mg, 0.062 mmol, 1.1 eq) were stirred in methanol (8 mL) overnightat room temperature. Sodium borohydride (31.8 mg, 0.084 mmol, 1.5 eq)was introduced and the reaction mixture stirred for 15 min. The reactionmixture was transferred to an ice bath and 2 drops of sodium hydroxide(2M) were added. Diethyl ether was added and the organic phase isolated.The aqueous layer was re-extracted with diethyl ether, organic layerscombined and washed with brine. The organic phase was then dried (MgSO₄)filtered and concentrated in vacuo to give crude material which wastaken to the next step without further purification.

Step 7b:(S)-Cyclohexyl-[4-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-aceticacid cyclopentyl ester (86)

Material from step 6b (50 mg, 0.083 mmol, 1 eq) was dissolved inDCM/methanol (2 mL: 2 mL) and stirred with TFA (1.0 mL) for 2 h. Theresulting salt was concentrated, dissolved in methanol and purified bypreparative HPLC to yield compound (86). LCMS purity 100%, m/z 502[M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.28-1.98 (26H, m, 13×CH₂),2.10-2.15 (2H, m, CH₂), 2.40 (2H, t, J=7.8 Hz, CH₂), 3.81 (1H, d, J=3.9Hz, CH), 4.21 (2H, m, CH₂), 5.01 (1H, s, CH), 5.23-5.25 (1H, m, CH),7.43 (2H, d, J=8.4 Hz, Ar—H), 7.68 (2H, d, J=8.7 Hz, Ar—H)

Synthesis of 92 and 93

Stage 1: 4-(3-Nitro-phenoxy)-butyric acid methyl ester

To a solution of 3-nitrophenol (8.35 g, 60 mmol), in DMF (50 ml) wasadded K₂CO₃ (16.56 g, 120 mmol) and methyl 1,4-bromobutyrate (11.95 g,66 mmol). The reaction was stirred at room temperature for 16 h. Thereaction was diluted with ethyl acetate and water. The organic phase wasseparated and washed with water (2×200 ml). The organic phase was driedwith Na₂SO₄ and concentrated in vacuo. The required ether was isolatedfollowing chromatography (ethyl acetate: heptane, 1: 9) as a pale yellowsolid (12.2 g, 85% yield). LCMS purity 100%, m/z 240 [M⁺+H]⁺.

Stage 2: 4-(3-Amino-phenoxy)-butyric acid methyl ester

Stage 1 nitro ester (250 mg, 1 mmol) was dissolved in ethanol (3 ml).Pd/carbon (40 mg) was added and the reaction stirred under a hydrogenatmosphere (balloon pressure) for 16 h. The reaction mixture wasfiltered through celite. The celite pad was washed with ethanol and thecombined organic fractions concentrated in vacuo to give the requiredproduct as an orange oil (210 mg, 100% yield). LCMS purity 89%, m/z 210[M⁺+H]⁺. The aniline was used in the next stage without furtherpurification.

Stage 3: Coupling to Resin

Suberic acid derivatised hydroxylamine 2-chlorotrityl resin (8 g, 7.52mmol, loading, 0.94 mmol/g) was swollen in DCM/DMF (80 ml/80 ml). PyBOP(11.8 g, 22.6 mmol) and diisopropylethylamine (13.1 ml, 75.2 mmol) wereadded to the flask followed by 4-(3-amino-phenoxy)-butyric acid methylester (4.73 g, 22.6 mmol). The reaction was shaken at room temperaturefor 72 h before standard wash and drying.

Stage 4: Ester Hydrolysis

Stage 3 resin (9.5 g), was suspended in THF/MeOH (34 ml/34 ml). NaOH(1.4 M, aq, 34 ml) was added and the reaction shaken for 16 h at roomtemperature. The resin was washed using the standard wash procedurebefore air drying.

Stage 5: Amino Acid Ester Coupling

Stage 4 resin (2.1 g), was suspended in DCM/DMF (20 ml/20 ml). PyBOP(3.1 g, 5.92 mmol), N-phenylglycine cyclopentyl ester (2.4 g, 5.92 mmol)and diisopropylethylamine (3.4 ml, 19.7 mmol) were added sequentiallyand the reaction shaken at room temperature for 72 hours. The resin wassubmitted to standard wash and dried.

Stage 6:(S)-{4-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-butyrylamino}-phenyl-aceticacid cyclopentyl ester (92)

Stage 5 resin bound cyclopentyl ester (1.1 g) was shaken with 2% TFA/DCM(10 ml) for 10 minutes before filtering the resin and evaporating thesolvent under reduced pressure at room temperature. The process wasrepeated (X³) and the combined crude product purified by preparativeHPLC to yield compound (92) (114 mg). LCMS purity 99%, m/z 568 [M⁺+H]⁺,¹H NMR (400 MHz, MeOD), δ: 1.40 (4H, m, 2×CH₂), 1.45-1.90 (13H, m,alkyl), 2.10 (4H, m, 2×CH₂), 2.40 (2H, t, CH₂), 2.50 (2H, m, CH₂), 4.00(2H, m, CH₂), 5.15 (1H, m, ), 5.40 (1H, s, NHCHCO), 6.65 (1H, m, Ar)7.15 (1H, m, Ar), 7.20 (1H, t, Ar), 7.30 (1H, s, Ar), 7.40 (5H, s, Ar).

Stage 7:(S)-{4-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-butyrylamino}-phenyl-aceticacid (93)

Stage 6 cyclopentyl ester resin (500 mg) was suspended in THF (15 ml).To the suspension was added NaOH (1.4M aq., 1.6 ml) and the reactionshaken for 16 hr at room temperature. The filtrate was removed and theresin washed and dried before cleavage. Cleavage was effected by shakingwith 2% TFA/DCM (5 ml) for 10 minutes before filtering the resin andevaporating the solvent under reduced pressure at room temperature. Theprocess was repeated (X³) and the combined crude product purified bypreparative HPLC to yield compound (93) (62 mg). LCMS purity 99%, m/z500 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.40 (4H, m, 2×CH₂), 1.60-1.80(4H, m, alkyl), 2.10 (4H, m, 2×CH₂), 2.40 (2H, t, CH₂), 2.50 (2H, t,CH₂), 4.00 (2H, m, CH₂), 5.45 (1H, s, NHCHCO), 6.65 (1H, d, Ar) 7.10(1H, m, Ar), 7.20 (1H, t, Ar), 7.25 (1H, s, Ar), 7.30-7.45 (5H, m, Ar).

Synthesis of 94 and 95

Stage 1: 3-nitro-benzyl-chroroformate Formation

To a solution of 3-nitro benzyl alcohol (10 g, 65 mmol), in dioxane(anhydrous, 100 ml) was added trichloromethyl chloroformate (9.47 ml, 78mmol). The reaction was heated at 75° C. under nitrogen for 16 h. Thesolvent was evaporated and the residue resuspended in dioxane andevaporated. The procedure was repeated (×3). The crude chloroformate wasused in the next stage without further purification.

Stage 2: (S)-2-(3-Nitro-benzyloxycarbonylamino)-3-phenyl-propionic acidcyclopentyl ester

L-Phe-cyclopentyl ester.TsOH salt (9.42 g, 23 mmol) was suspended in DCM(40 ml). Triethylamine (6.5 ml, 47 mmol) was added and the reactionstirred at room temperature for 5 min. Stage 1 chloroformate (5 g, 23mol) dissolved in DCM (10ml) was added to the reaction mixture addeddropwise with cooling (ice bath). The reaction was stirred for 16 h atroom temperature. The solvent was removed and the residue dissolved inEtOAc (100 ml) washed with water (50 ml×3) and dried (Na₂SO₄) beforeconcentration in vacuo. The crude material was purified bychromatography (EtOAc: heptane, 1: 9) to give the required carbamate(6.4 g, 67% yield). m/z 413 [M⁺+H]⁺

Stage 3: (S)-2-(3-Amino-benzyloxycarbonylamino)-3-phenyl-propionic acidcyclopentyl ester

Stage 2 nitro carbamate (6.4 g, 15.5 mmol) was dissolved in ethanol (64ml). Tin chloride dihydrate (17.5 g, 77 mmol) was added and the reactionstirred for 16 h at room temperature. The solvent was evaporated and theresidue dissolved in EtOAc (60 ml). A saturated solution of sodiumpotassium tartrate (60 ml) was added followed by a solution of saturatedsodium hydrogen carbonate (120 ml). The biphasic solution was stirredfor 15 min. The organic layer was separated and the aqueous phaseextracted with EtOAc (60 ml xl). The organic layers were combined, driedand the solvent evaporated to give the crude product which was purifiedby chromatography (EtOAc: heptane 1:3→1:1). The required product wasisolated (3.5 g, 59% yield). LCMS purity 100%, m/z 383 [M⁺+H]⁺.

Stage 4: Coupling to Resin

Suberic acid derivatised hydroxylamine 2-chlorotrityl resin (2.0 g, 1.88mmol, loading, 0.94 mmol/g) was swollen in DMF (20 ml). PyBOP (2.93 g,5.64 mmol) and diisopropyl ethylamine (3.25 ml, 18.8 mmol) were added.Stage 3 anilino carbamate (1.8 g, 4.7 mmol) dissolved in DCM (20 ml) wasadded and the reaction shaken for 4 d before filtrate removal andstandard wash of the resin which was dried under air.

Stage 5:(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzyloxycarbonylamino]-3-phenyl-propionicacid cyclopentyl ester (94)

Stage 4 resin bound cyclopentyl ester (2 g) was shaken with 2% TFA/DCM(15 ml) for 10 minutes before filtering the resin and evaporating thesolvent under reduced pressure at room temperature. The process wasrepeated (×³) and the combined crude product purified by preparativeHPLC to yield compound (94). LCMS purity 95%, m/z 554 [M⁺+H]⁺, ¹H NMR(400 MHz, MeOD), δ: 1.30 (4H, m, 2×CH₂), 1.40-1.90 (13H, m, alkyl), 2.00(2H, t, CH₂), 2.30 (2H, t, CH₂), 2.90 (2H, ddd, CH₂), 3.80 (1H, m), 4.25(1H, dd, NHCHCO), 4.90 (2H, s, CH₂), 5.05 (1H, m), 5.35 (1H, m), 6.95(1H, d, Ar) 7.05-7.25 (6H, m, Ar), 7.35-7.75 (2H, m, Ar).

Stage 6:(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzyloxycarbonylamino]3-phenyl-propionicacid (95)

Compound (94) (100 mg, 0.18 mmol) was dissolved in THF (1 ml) and 2MNaOH (1 ml) added. The reaction vial was shaken for 4 h before THFremoval via a stream of nitrogen. The aqueous residue was purified bypreparative HPLC to yield compound (95) (62 mg). LCMS purity 95%, m/z486 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.35 (4H, m, 2×CH₂), 1.55-1.75(4H, m, alkyl), 2.10 (2H, t, CH₂), 2.35 (2H, t, CH₂), 2.95 (2H, dd, CH),3.20 (1H, dd, CH), 4.45 (1H, dd, NHCHCO), 5.00 (2H, s, CH₂), 7.05 (1H,d, Ar), 7.20-7.35 (6H, m, Ar), 7.55 (2H, m, Ar).

Synthesis of Compound (96) and Compound (97)

Stage 1: (S)-7-Nitro-1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid

Prepared as described in Teft Letts 42, 2001, 3507.

Stage 2: (S)-7-Nitro-3,4-dihydro-1H-isoquinoline-2,3-dicarboxylicacid-2-tert-butyl ester

(S)-7-Nitro-1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid (7 g, 31.5mmol) was dissolved in THF:water (1:1, 350 ml). K₂CO₃ was added (5.2 g,37 mmol) followed by boc anhydride (13.7 g, 63 mmol) and the solutionheated at 40° C. for 1 h. THF was removed by evaporation and the aqueouslayer adjusted to pH=7 before extraction with EtOAc. The organic layerwas washed 0.1 M HCl (×³) and dried over Na₂SO₄ before concentration invacuo. The required N-protected product was obtained following columnchromatography (EtOAc: heptane 2: 3 EtOAc), (7.5 g, 74%), LCMS purity92%, molecular ion not observed

Stage 3:(S)-3-((S)-1-Cyclopentyloxycarbonyl-3-methyl-butylcarbamoyl)-7-nitro-3,4-dihydro-1H-isoquinoline-2-carboxylicacid tert-butyl ester

(S)-7-Nitro-3,4-dihydro-1H-isoquinoline-2,3-dicarboxylicacid-2-tert-butyl ester (2.5 g, 7.76 mmol) was dissolved in DCM (100ml). HOBt (1.16 g, 8.53 mmol) was added, L-leucine cyclopentyl ester(3.19 g, 8.53 mmol) was added followed by triethylamine (2.38 ml, 17.1mmol). EDCI.HCl (1.46 g, 8.5 mmol) was added and the reaction stirred atroom temperature for 16 h. To the reaction was added DCM (100 ml) andthe organic layer washed with water (3×300 ml), dried with Na₂SO₄ andthe solvent removed in vacuo. The crude product was purified bychromatography (EtOAc: heptane 1: 2 EtOAc) to give the required product3.14 g (82% yield), LCMS purity 100%, m/z 504 [M⁺+H]⁺

Stage 4:(S)-7-Amino-3-((S)-1-cyclopentyloxycarbonyl-3-methyl-butylcarbamoyl)-3,4-dihydro-1H-isoquinoline-2-carboxylicacid tert-butyl ester

(S)-3-((S)-1-Cyclopentyloxycarbonyl-3-methyl-butylcarbamoyl)-7-nitro-3,4-dihydro-1H-isoquinoline-2-carboxylicacid tert-butyl ester (3.14 g, 6.24 mmol) and Pd/carbon (0.4 g) weresuspended in EtOAc (20 ml). The reaction was stirred under a hygrogenatmosphere (balloon pressure) for 16 h. The solution was filteredthrough a pad of celite and the solvent removed. The crude product (3.04g) was used in the next step without further purification. LCMS purity83%, m/z 474 [M⁺+H]+

Stage 5: Coupling to Resin

Suberic acid derivatised hydroxylamine 2-chlorotrityl resin (2.2 g,loading, 0.94 mmol/g) was swollen in DCM/DMF (1:1, 80 ml). PyBOP (3.20g, 6.15 mmol) and diisopropylethylamine (3.54 ml, 20.7 mmol) were added.Stage 3 anilino amide (3.04 g, 6.43 mmol) dissolved in DMF (40 ml) wasadded and the reaction shaken for 3 days before filtrate removal andstandard wash of the resin which was dried under air.

Stage 6:(S)-2-{[(S)-7-(7-Hydroxycarbamoyl-heptanoylamino)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-4-methyl-pentanoicacid cyclopentyl ester (96)

Stage 5 resin bound cyclopentyl ester (600 mg) was shaken with 2%TFA/DCM (8 ml) for 30 minutes before filtering the resin and evaporatingthe solvent under reduced pressure at room temperature. The crudeproduct was purified by preparative HPLC to yield(S)-2-{[(S)-7-(7-Hydroxycarbamoyl-heptanoylamino)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-4-methyl-pentanoicacid cyclopentyl ester (17.5 mg). The boc group is removed in additionto resin cleavage. LCMS purity 98%, m/z 545 [M⁺+H]⁺, ¹H NMR (400 MHz,MeOD), δ: 0.85-0.88 (6H, 2×d, J=6.4 Hz, J=6.5 Hz, 2×CH₃), 1.30 (4H, m,alkyl), 1.50-1.65 (13H, m, alkyl), 1.80 (2H, m, CH₂), 1.95 (2 H, t,CH₂), 2.25 (2H, t, CH₂), 3.00 (1H, m, CH), 3.25 (1H, m, CH), 4.10 (1H,m, CH), 4.25 (2H, s, CH₂), 4.29 (1H, m, CH), 5.10 (1H, m, CH), 7.11 (1H,d, J=8.4 Hz, Ar), 7.25 (1H, d, J=8.3 Hz, Ar), 7.55 (2H, m, Ar).

Stage 7:(S)-2-{[(S)-7-(7-Hydroxycarbamoyl-heptanoylamino)-1,2,3,4-tetrahydro-isoquinoline-3-carbonyl]-amino}-4-methyl-pentanoicacid (96)

Stage 5 cyclopentyl ester resin (1.55 g) was suspended in THF/MeOH (10ml /10 ml). To the suspension was added NaOH (1.4 M aq., 5 ml) and thereaction shaken for 16 hr at r.t. The filtrate was removed and the resinwashed (standard) and dried before cleavage. Cleavage (600 mg of resin)was effected by shaking with 2% TFA/DCM (8 ml) for 30 minutes beforefiltering the resin and evaporating the solvent under reduced pressureat room temperature. The crude product purified by preparative HPLC toyield Compound (97) (73.4 mg). The boc group is removed in addition toresin cleavage. LCMS purity 96%, m/z 477 [M⁺+H]⁺, ¹H NMR (400 MHz,MeOD), δ: 0.98-1.02 (6H, 2×d, J=6 Hz, J=6.1 Hz, 2×CH₃), 1.40 (4H, m,alkyl), 1.60-1.80 (7H, m, alkyl), 2.10 (2H, t, J=7.4 Hz, CH₂), 2.39 (2H,t, 7.6 Hz, CH₂), 3.15 (1H, dd, J=12.5 Hz, J=16.6 Hz, CH), 3.45 (1H, dd,J=4.9 Hz, J=17 Hz, CH) 4.00 (1H, s, CH), 4.20 (1H, dd, J=4.7 Hz, J=12.2Hz, CH), 4.40 (2H, m, CH₂), 4.55 (1H, dd, J=4.7 Hz, J=10 Hz, CH), 7.25(1H, d, J=8.4 Hz, Ar), 7.25 (1H, d, J=8 Hz, Ar), 7.55 (1 H, J=7 Hz, Ar).

Synthesis of Compound (98) and Compound (99)

Stage 1: (S)-4-Methyl-2-(4-nitro-benzoylamino)-pentanoic acidcyclopentyl ester

L-leucine cyclopentyl ester. TsOH salt (7.98 g, 21.51 mmol) wasdissolved in THF (40 ml) and triethylamine (6 ml, 21.5 mmol) added.4-Nitrobenzoyl chloride (4 g, 21.5 mmol) was added portionwise withcooling, ice bath. The reaction was stirred at room temperature for 16 hbefore evaporation to dryness. The residue was dissolved in DCM (100 ml)and washed with saturated sodium hydrogen carbonate (3×100 ml), 1 M HCl(3×100 ml) and brine, dried (Na₂SO₄), and the solvent removed in vacuo.to give the required product 5.25 g (70% yield) which was used in thenext step without further purification, LCMS purity 100%, m/z 349[M⁺+H]⁺

Stage 2: (S)-2-(4-Amino-benzoylamino)-4-methyl-pentanoic acidcyclopentyl ester

Stage 1 nitro amide (5.25 g, 15.1 mmol) was dissolved in ethanol (100ml). Pd/carbon (200 mg) was added and the reaction stirred for 16 h atroom temperature under hydrogen (balloon pressure). The reaction mixturewas filtered through celite and evaporated to give the required amineamide 3.9 g (81% yield) which was used in the next step without furtherpurification, LCMS purity 100%, m/z 319 [M⁺+H]+

Stage 3: Coupling to Resin

Suberic acid derivatised Wang hydroxylamine resin (1.6 g, loading, 1.8mmol/g) was swollen in DCM (anhydrous, 20 ml).1-Chloro-N,N-2-trimethylpropenylamine (1.15 ml, 8.64 mmol) was addeddropwise before shaking at room temperature for 1 h.(S)-2-(4-Amino-benzoylamino)-4-methyl-pentanoic acid cyclopentyl ester(2.75 g, 8.64 mmol) was added followed by triethylamine (2.4 ml, 17.63mmol) and the reaction shaken at room temperature for 16 h. The resinwas washed (standard) and air dried.

Stage 4:(S)-2-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-4-methyl-pentanoicacid cyclopentyl ester (98)

Stage 3 resin bound cyclopentyl ester was shaken with 2% TFA/DCM (10 ml)for 10 minutes before filtering the resin and evaporating the solventunder reduced pressure at room temperature. The process was repeated(×3) and the combined crude product purified by preparative HPLC toyield compound (98) (36 mg). LCMS purity 91%, m/z 490 [M⁺+H]⁺, ¹H NMR(400 MHz, MeOD), δ: 0.80-0.95 (6H, 2×CH₃), 1.25 (4H, m, alkyl),1.40-1.85 (15H, m, alkyl), 2.00 (2H, t, CH₂), 2.30 (2H, t, CH₂), 4.45(1H, m, CH), 5.05 (1H, m, CH), 7.60 (2H, d, Ar), 7.75 (2H, d, Ar).

Stage 5:(S)-2-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzoylamino]-4-methyl-pentanoicacid (99)

Compound (98) (21 mg, 0.043 mmol) was dissolved in THF (1 ml) and 2MNaOH (1 ml) added. The reaction vial was shaken for 16 h before THFremoval by blowing a stream of N₂ gas at the surface of the solution.The aqueous residue was purified by preparative HPLC to yield compound(99) (5.2 mg). LCMS purity 92%, m/z 422 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD),δ: 0.95-1.05 (6H, m, 2×CH₃), 1.30-1.50 (4 H, m, alkyl), 1.55-1.85 (7H,m, alkyl), 2.10 (2H, t, CH₂), 2.40 (2H, t, CH₂), 4.65 (1 H, m, CH), 7.65(2H, d, Ar), 7.80 (2H, d, Ar).

Synthesis of Compound (100) and Compound (101)

Stage 1: 5-((E)-2-Ethoxycarbonyl-vinyl)-1H-indole-2-carboxylic acid

5-Bromoindole-2-carboxylic acid (400 mg, 1.66 mmol) and tri-O-tolylphosphine (96 mg, 0.32 mmol) were added to a microwave tube. Ethylacrylate (0.56 ml, 5.6 mmol), Et₃N (0.92 ml, 6.6 mmol), acetonitrile(2.5 ml) and Pd(OAc)₂ (40 mg, 0.18 mmol) were added. The reaction wasplaced in a CEM microwave at 150 W, 90° C. for 30 minutes with 5 minramp time. EtOAc was added and the reaction mixture filtered throughcelite. The celite pad was washed with DCM and the combined organicfractions removed to give a yellow solid. The solid was redissolved inDCM and extracted into saturated sodium hydrogen carbonate. The aqueouslayer was washed with DCM and diethyl ether. The aqueous basic layer wasacidified with 2M HCl (pH=5) and the product extracted into EtOAc. Thesolvent was removed to give the required product (370 mg, 86% yield).LCMS purity 86%, m/z 260 [M⁺+H]⁺

Stage 2: 5-((E)-2-Ethoxycarbonyl-vinyl)-1H-indole-2-carboxylic acid

5-((E)-2-Ethoxycarbonyl-vinyl)-1H-indole-2-carboxylic acid (430 mg, 1.66mmol) was dissolved in EtOAc (100 ml). Pd/carbon (100 mg) was added andthe reaction stirred under a hydrogen atmosphere (balloon pressure) for18 h. The reaction mixture was filtered through a pad of celite andwashed with EtOAc. The solvent was removed to give the required productwhich was used in the next step without further purification (0.47 g).LCMS purity 92%, m/z 262 [M⁺+H]⁺

Stage 3:3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionicacid ethyl ester

5-((E)-2-Ethoxycarbonyl-vinyl)-1H-indole-2-carboxylic acid (0.427 g, 1.6mmol) was dissolved in anhydrous DMF (20 ml). EDCI.HCl (0.38 g, 2 mmol),Et₃N (0.59 ml, 4.3 mmol), HOBt (0.27 g, 2 mmol) and 7 amino heptanoicacid (tetrahydropyran-2-yloxy) amide (0.4 g, 1.6 mmol in anhydrous DMF20 ml) were added and the reaction stirred at room temperature for 16 hunder nitrogen. Water was added, the reaction mixture acidified topH=6-7 (10% citric acid) and extracted with DCM. The organic layer waswashed with 10% citric acid and saturated sodium hydrogen carbonate(X²). The solvent was removed in vacuo to give crude product which waspurified by chromatography (EtOAc:hexane 1:2→EtOAc) to give the requiredproduct as a yellow solid (550 mg, 69% yield). LCMS purity 93%, m/z 488[M⁺+H]⁺

Stage 4:3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionicacid

3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionicacid ethyl ester (550 mg, 1.13 mmol) was dissolved in THF/methanol (50mli/25 ml). 1.4 M NaOH solution (50 ml) was added and the reactionstirred at room temperature for 4 h. The solvent was reduced to ˜50%volume and 1 M HCl added to pH 6-7. The mixture was extracted with DCMand further extracted with EtOAc. The combined organic layer was dried,Na₂SO₄ and the solvent removed in vacuo to give the required product 357mg (69% yield) as a yellow powder which was used in the next stepwithout further purification. LCMS purity 94%, m/z 460 [M⁺+H]⁺

Stage 5:(S)-3-Phenyl-2-(3-{2-[6-(tetrahydro-pyran-2-yloxycarbamoyl)-hexyl-carbamoyl]-1H-indol-5-yl}-propionylamino)-propionicacid cyclopentyl ester

3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionicacid (0.357 g, 0.78 mmol) was dissolved in DCM/DMF (20 ml/20 ml).EDCI.HCl (0.163 mg, 0.86 mmol), triethylamine (0.24 ml, 1.7 mmol), HOBt(0.116 mg, 0.88 mmol) and L-phenylalanine cyclopentyl ester.TsOH salt(0.346 mg, 0.88 mmol) were added and the reaction mixture stirred for 16h at room temperature under nitrogen. The solvent volume was reduced(˜10 ml), DCM was added and the organic layer washed with water (X³).The organic layer was dried (Na₂SO₄) and the solvent removed to give therequired product (500 mg, 95% yield) which was used without furtherpurification. LCMS purity 77%, m/z 675 [M⁺+H]⁺

Stage 6:(S)-2-{3-[2-(6-Hydroxycarbamoyl-hexylcarbamoyl)-1H-indol-5-yl]-propionylamino}-3-phenyl-propionicacid cyclopentyl ester (100)

(S)-3-Phenyl-2-(3-{2-[6-(tetrahydro-pyran-2-yloxycarbamoyl)-hexyl-carbamoyl]-1H-indol-5-yl}-propionylamino)-propionicacid cyclopentyl ester (200 mg. 0.297 mmol) was stirred at roomtemperature for 3.5 h in TFA/DCM/MeOH (1.5 ml/15 ml/15 ml). Further TFA(0.3 ml) was added and the reaction stirred for a further 30 minutes.The solution was concentrated in vacuo, resuspended in DCM and thesolvent removed (X³). The crude material was purified by prep HPLC togive pure compound (100) (19.3 mg), LCMS purity 100%, m/z 591 [M⁺+H]⁺,¹H NMR (400 MHz, MeOD), δ: 1.27-1.70 (16 H, m, alkyl), 1.97 (2H, t,CH₂), 2.40 (2H, t, J=7.84 Hz, CH₂), 2.76-2.85 (4H, m, 2×CH₂), 3.25 (2H,t, J=7 Hz, CH₂), 4.41 (1H, m, NHCHCO, 4.95 (1H, m, CH), 6.85 (1 H, s,CH), 6.95 (3H, m, Ar), 7.05 (3H, m, Ar), 7.20-7.26 (2H, s+d, J=8.5 Hz,Ar)

Stage 7:(S)-2-{3-[2-(6-Hydroxycarbamoyl-hexylcarbamoyl)-1H-indol-5-yl]-propionylamino}-3-phenyl-propionicacid (101)

Compound (100) (80 mg, 0.14 mmol) was dissolved in THF/MeOH (1 ml/0.5ml) and 1.4 M NaOH (0.5 ml) added. The reaction was stirred at roomtemperature for 2 h. THF was removed by blowing a stream of N₂ gas atthe surface of the solution and the residual material purified bypreparative HPLC to give compound (101) (34.9 mg),

LCMS purity 95%, m/z 523 [M⁺+H]⁺, ¹H NMR (400 MHz, MeOD), δ: 1.35-1.50(4H, m, alkyl), 1.60-1.75 (4H, m, alkyl), 2.15 (2H, brt, CH₂), 2.55 (2H,brt, CH₂), 2.95 (3 H, m, CH+CH₂), 3.10 (1H, dd, CH), 4.65, (1H, m,NHCHCO), 7.00-7.15 (7H, m, Ar), 7.35-7.41 (2H, m, Ar)

*Preparation of 7 amino heptanoic acid (tetrahydropyran-2-yloxy) amide

Stage 1: 6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexyl]-carbamic acid9H-fluoren-9-ylmethyl ester

To a solution of 7-(9H-fluoren-9-yloxycarbonylamino) heptanoic acid (1g, 2.72 mmol) in anhydrous DCM/THF (15 ml/15 ml) was added EDCI. HCl(627 mg, 3.27 mmol), HOBt (442 mg, 3.27 mmol) andO-(tetrahydro-pyran-2-yl)-hydroxylamine (383 mg, 3.27 mmol) which wasstirred under nitrogen for 48 h. EDCI. HCl (260 mg, 1.36 mmol), HOBt(184 mg, 1.36 mmol) and O-(tetrahydro-pyran-2-yl)-hydroxylamine (159 mg,1.36 mmol) were added and the reaction continued for a further 24 h. Thereaction mixture was diluted with DCM (100 ml), washed with water (3×100ml), brine (100 ml), dried (Na₂SO₄), filtered and concentrated in vacuo.Purification by chromatography (MeOH:DCM 2:98) gave a white solid (1.03g, 81%).

Stage 2: 7-Amino-heptanoic acid tetrahydro-pyran-2-yl ester

6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexyl]-carbamic acid9H-fluoren-9-ylmethyl ester (300 mg, 0.644 mmol) was dissolved in 20%piperidine/DCM (30 ml) and the reaction stirred for 0.5 h. The reactionwas evaporated to dryness, redissolved in DCM and evaporated (×3). Therequired product was obtained following chromatography (MeOH:DCM:NH₃),120 mg. LCMS purity 98%, m/z 245 [M⁺+H]⁺.

Synthesis of Compound (102) and Compound (103)

Stage 1: Resin Loading

Wang hydroxylamine resin (3.72 g, 1.8 mmol/g) was swollen in DMF (50ml). HATU (7.5 g, 19.7 mmol), 5-nitro-1-benzothiophene-2-carboxylic acid(3 g, 13.45 mmol, dissolved in DMF 150 ml) and diisopropylethylamine(4.65 ml, 26.7 mmol) were added and the resin shaken at room temperaturefor 4 d. The resin was filtered and washed using the standard washingprocedure and air dried.

Stage 2: Nitro Reduction

Stage 1 resin (4.9 g, 1.8 mmol/g), was swollen in DMF (200 ml) and tinchloride dihydrate (19.9 g, 88 mmol) added. The reaction was shaken atroom temperature for 16 h. The resin was filtered and washed using thestandard washing procedure and air dried.

Stage 3: 4-(4-Benzyloxycarbonylmethyl-phenoxy)-butyric acid methyl ester

Benzyl 4-hydroxyphenyl acetate (9 g, 37 mmol) was dissolved in DMF (300ml). Ground sodium hydroxide (2.23 g, 56 mmol) and 4-methyl bromobutyrate (6.4 ml, 56 mmol) were added and the reaction heated at 60° C.for 16 h. Water was added to the cooled reaction mixture and thesolution acidified (pH=5/6) with 1 M HCl. The aqueous layer wasextracted with EtOAc and the organic layer washed with water (X²), driedover Na₂SO₄, filtered and evaporated to dryness. The required diesterwas obtained following chromatography (EtOAc: heptane 1:2), (9.56 g,75%) LCMS purity 90%, m/z 343 [M⁺+H]⁺.

Stage 4: 4-(4-Carboxymethyl-phenoxy)-butyric acid methyl ester

4-(4-Benzyloxycarbonylmethyl-phenoxy)-butyric acid methyl ester (1.4 g,4.09 mmol) was dissolved in EtOAc (60 ml). Pd/carbon (100 mg) was addedand the reaction stirred under a hydrogen atmosphere (balloon) for 16 hat room temperature. The reaction mixture was filtered through a pad ofcelite and the pad washed with EtOAc. The filtrate was evaporated todryness to give a white solid (1.03 g, 100% yield). LCMS purity 93%, m/z253 [M⁺+H]⁺.

Stage 5: Coupling to Resin

Stage 2 resin (0.18 g, 1.8 mmol/g) was swollen in DMF (5 ml). HATU (0.37g, 0.96 mmol), 4-(4-Carboxymethyl-phenoxy)-butyric acid methyl ester(0.247 g, 0.96 mmol dissolved in DMF-10 ml) and diisopropylamine (0.56ml, 3.3 mmol) were added and the reaction shaken at room temperature for16 h. The reaction was filtered and the resin washed using the standardwash procedure and air dried.

Stage 6: Ester Hydrolysis

Stage 5 methyl ester (280 mg, 1.8 mmol/g) was dissolved in THF/MeOH (4ml/4 ml) and 1.4 M NaOH (8 ml) added. The reaction was shaken at r.t.for 16 h. The resin was filtered and washed using the standard wash andair dried.

Stage 7: Amino Acid Coupling

Stage 6 resin (1.6 g, 1.8 mmol/g) was swollen in anhydrous DMF (120 ml).HATU (3.3 g, 8.6 mmol), L-phenylalanine cyclopentyl ester. TsOH salt(3.4 g, 8.6 mmol) and diisopropylamine (5 ml, 2.9 mmol) were added andthe reaction shaken at room temperature for 16 h. The reaction wasfiltered and the resin washed using the standard wash procedure and airdried.

Stage 8:(S)-2-(4-{4-[(2-Hydroxycarbamoyl-benzo[b]thiophen-5-ylcarbamoyl)-methyl]-phenoxy}-butyrylamino)-3-phenyl-propionicacid cyclopentyl ester (102)

Stage 7 resin bound cyclopentyl ester was shaken with 2% TFANDCM (10 ml)for 10 minutes before filtering the resin and evaporating the solventunder reduced pressure at room temperature. The process was repeated(X³) and the combined crude product purified by preparative HPLC toyield compound (102) (22.5 mg). LCMS purity 99%, m/z 644 [M⁺+H]⁺, ¹H NMR(400 MHz, MeOD), δ: 1.45-1.80 (6H, m, alkyl), 1.95 (2H, pent, CH₂), 2.34(2H, t, J=7.3 Hz, CH₂), 2.90 (1H, dd, CH), 3.04 (1H, dd, CH), 3.62 (2H,s, CH₂), 3.86, (2H, m, CH₂), 4.55 (1H, m, NHCHCO), 5.07 (1H, br s, CH),6.83 (2H, d, J=8.3 Hz, Ar), 7.14-7.18 (5H, m, Ar), 7.25 (2H, d, J=8 Hz,Ar), 7.47 (1H, d, J=9 Hz, Ar), 7.73 (1H, s, Ar), 7.81 (1H, d, J=8.8 Hz),8.25 (1H, s, Ar)

Stage 9:(S)-2-(4-{4-[(2-Hydroxycarbamoyl-benzo[b]thiophen-5-ylcarbamoyl)-methyl]-phenoxy}-butyrylamino)-3-phenyl-propionicacid (103)

Stage 7 cyclopentyl ester resin (200 mg) was swollen in THF/MeOH (2 ml/2ml) and 1.4 M NaOH (2 ml) added. The reaction was shaken at roomtemperature for 16 h. The resin was filtered and washed using thestandard wash. Resin bound carboxylic acid was shaken with 2% TFA/DCM (3ml) for 10 minutes before filtering the resin and evaporating thesolvent under reduced pressure at room temperature. The process wasrepeated (×3) and the combined crude product purified by preparativeHPLC to yield compound (103) (33.7 mg). LCMS purity 88%, m/z 576[M⁺+H]⁺, ¹H NMR (400 MHz, d6-DMSO), 6:1.93 (2H, m, CH₂), 2.30 (2H, m,CH₂), 2.91 (1H, dd, J=9.9 Hz, J=13.8 Hz, CH), 3.13 (1H, dd, J=4.8 Hz,J=13.9 Hz, CH), 3.67 (2H, s, CH₂), 3.91, (2H, m, CH₂), 4.50 (1H, m,NHCHCO), 6.92 (2H, d; J=8.7 Hz, Ar), 7.24-7.34 (7H, m, Ar), 7.61 (1H,m), 7.92 (1H, br s, Ar), 8.00 (1H, d, J=8.8 Hz, Ar), 8.31 (1H, d, J=8.1Hz, Ar), 8.39 (1H, s), 9.36 (1H, brs), 10.36 (1H, s), 11.52 (1H, s),12.76 (1H, br s)

Synthesis of Compounds in FIG. 7 as Exemplified for Compound (104) andCompound (105)

Step 1: 4-(tert-Butoxycarbonylamino-methyl)-benzoic acid

4-Aminomethylbenzyl alcohol (1.0 g, 6.60 mmol) was slurried in a mixtureof THF (10 mL) and water (10 mL). A solution of saturated sodiumhydrogen carbonate was added until the pH of the solution was >pH 9. Themixture was cooled to 0° C. and di-tert-butyldicarbonate (2.89 g, 13.23mmol) added. The reaction was allowed to stir overnight then THF removedunder vacuum. The aqueous mixture was extracted with EtOAc (20 mL) andthen acidified to pH 3 by addition of 1 N HCl. This was extracted withEtOAc (2×10 mL), the organic layers combined, dried (MgSO₄) andevaporated to dryness to afford the desired product (1.60 g, 97%). m/z252 [M⁺+H]⁺

Step 2: (4-Hydroxymethyl-benzyl)-carbamic acid tert-butyl ester

LiAl₄ (227 mg, 5.97 mmol) was slurried in a mixture of THF (5 mL) anddioxane (5 mL) and cooled to 0° C. under an atmosphere of N₂.4-(tert-Butoxycarbonylamino-methyl)-benzoic acid was dissolved in amixture of THF (5 mL) and dioxane (5 mL) and added to the chilledsolution drop-wise over 15 min. The reaction mixture was allowed to warmto r.t and stirred for 16 h. Water (1 mL) was added to the reactionmixture which was then filtered through celite. The filtrate wasevaporated to dryness and the residue partitioned between EtOAc (25 mL)and water (25 mL). The aqueous layer was extracted with EtOAC (2×25 mL),the organic layers combined, dried (Na₂SO₄) and evaporated to dryness toafford the desired product (460 mg, 100%). m/z 260 [M⁺+Na]⁺

Step 3: (4-Formyl-benzyl)-carbamic acid tert-butyl ester

(4-Hydroxymethyl-benzyl)-carbamic acid tert-butyl ester (480 mg, 0.71mmol) was dissolved in DCM (3 mL) and cooled to −78° C. (dryice/acetone). Dess-Martin periodinane (331 mg, 0.78 mmol) was added tothe reaction which was allowed to warm to r.t and stir for 3 h. A 1:1solution of saturated sodium bicarbonate and sodium sulfite (20 mL) wasadded and the reaction mixture stirred vigorously for 15 min. Theorganic layer was isolated, washed with saturated sodium bicarbonate (10mL), dried (Na₂SO₄) and evaporated to dryness to afford the desiredcompound (480 mg, 100%). m/z 258 [M⁺+Na]⁺

Step 4:(S)-2-[4-(tert-Butoxycarbonylamino-methyl)-benzylamino]-3-phenyl-propionicacid cyclopentyl ester

(4-Formyl-benzyl)-carbamic acid tert-butyl ester (200 mg, 0.85 mmol) wasdissolved in DCE (10 mL) and to this was added phenyl alaninecyclopentyl ester (214 mg, 0.94 mmol). The reaction was stirred at r.t.for 15 min. Sodium triacetoxyborohydride (538 mg, 2.55 mmol) and aceticacid (60 uL) were added and the reaction stirred for a further 1 h.Saturated sodium bicarbonate (10 ml) was added and the solution dilutedwith DCM (20 mL). The organic layer was isolated and concentrated toafford the desired product which was taken onto the next step withoutfurther purification. m/z 453 [M⁺+H⁺

Step 5: (S)-2-(4-Aminomethyl-benzylamino)-3-phenyl-propionic acidcyclopentyl ester

(S)-2-[4-(tert-Butoxycarbonylamino-methyl)-benzylamino]-3-phenyl-propionicacid cyclopentyl ester was treated with 4M HCl in dioxane (1 mL, 0.25mmol) and stirred at r.t. for 1 h. The mixture was evaporated to drynessand partitioned between EtOAc (20 mL) and water (20 mL). Saturatedsodium bicarbonate (20 mL) was added to the aqueous layer which was thenextracted with EtOAc (3×20 mL). The organic layers were combined, dried(Na₂SO₄) and evaporated to dryness to give the desired product (263 mg,79% over 2 steps). m/z 353 [M⁺+H]⁺

Step 6:(S)-2-[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-benzylamino]-3-phenyl-propionicacid cyclopentyl ester

6-formyl-benzo[b]thiophene-2-carboxylic acid (1-isobutoxy-ethoxy) amide(Scheme 7) (220 mg, 0.68 mmol) and(S)-2-(4-Aminomethyl-benzylamino)-3-phenyl-propionic acid cyclopentylester (263 mg, 0.75 mmol) were dissolved in DCE (10 mL) under anatmosphere of N₂. Sodium triacetoxyborohydride (430 mg, 2.04 mmol) andacetic acid (50 μL) were added and the reaction stirred at r.t for 3 h.Sodium hydrogen carbonate (20 mL) was added and the reaction mixtureextracted with dichloromethane (3×50 mL). The organic layers werecombined and concentrated. The residue was purified by columnchromatography (50%-100% EtOAc/heptane) to give the protected compound(80 mg, 21%). m/z 658 [M⁺+H]⁺

Step 7:(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-3-phenyl-propionic acid cyclopentyl ester (104)

(S)-2-[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-benzylamino]-3-phenyl-propionicacid cyclopentyl ester was dissolved in DCM (2 mL) and MeOH (2 mL) andtreated with TFA (1 mL). The mixture was stirred for 1 h at r.t thenconcentrated to dryness and DCM (5 mL) and heptane (5 mL) added. Themixture was evaporated to dryness. This process was repeated three timesto yield compound (104) (20 mg, 59%) as a oil. LCMS purity 95%, m/z 558[M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.25-1.91 (8H, m, 4×CH₂), 3.12-3.47(2H, m, CH₂), 4.26 (1H, m, CH), 4.33 (2H, d, J=5.5 Hz, CH₂), 4.36 (2H,s, CH₂), 4.43 (1H, s, CH₂), 5.16 (1H, s, CH), 5.13 (1H, m, CH),7.25-7.37 (6H, m, ArH), 7.54-7.63 (4H, m, ArH), 7.94 (2H, m, ArH), 8.09(1H, s, ArH).

Step 8:(S)-2-[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-benzylamino]-3-phenyl-propionicacid

(S)-2-[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-benzylamino]-3-phenyl-propionicacid cyclopentyl ester (40 mg, 0.06 mmol) was dissolved in THF (2 mL)and water (2 mL). LiOH (8 mg, 0.30 mmol) was added and the reactionmixture heated to 50° C. for 36 h. THF was removed by evaporation andthe residue partitioned between water (10 mL) and EtOAc (10 mL). Theaqueous layer was isolated and the pH adjusted to 3 by addition of 1 MHCl. This was extracted with EtOAc (3×20 mL), the organic layerscombined and evaporated to dryness.

Step 9:(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-3-phenyl-propionic (105)

(S)-2-[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-benzylamino]-3-phenyl-propionicacid was dissolved in MeOH (2 mL) and THF (2 mL). TFA (1 mL) was addedat the mixture stirred for 1 h at r.t. The reaction mixture wasconcentrated to dryness and DCM (5 mL) and heptane (5 mL) added. Themixture was evaporated to dryness. This process was repeated three timesto yield compound (105) (17 mg, 57%) as a pink solid. LCMS purity 90%,m/z 490 [M⁺+H]⁺, 1H NMR (300 MHz, MeOD), δ: 3.33 (2H, m, CH₂), 4.19 (1H,m, CH₂), 4.29 (2H, s, CH₂), 4.35 (2H, s, CH₂), 4.42 (2H, s, CH₂),7.29-7.39 (5H, m, ArH), 7.54-7.72 (5H, m, ArH), 7.88 (1H, s, ArH), 8.00(1H, d J=8.0 Hz, ArH), 8.08 (1H, s, ArH)

The following compounds were prepared according to the proceduredescribed for compound (104) and compound (105)

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-3-(4-hydroxy-phenyl)-propionicacid cyclopentyl ester (106)

LCMS purity 98%, m/z 574 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.30-1.87(8H, m, 4×CH₂), 2.97-3.35 (2H, m, CH₂), 4.17 (1H, m, CH), 4.31 (2H, d,J=5.4 Hz, CH₂), 4.36 (2H, s, CH₂), 4.42 (2H, s, CH₂), 5.11-5.16 (1H, m,CH), 6.77 (2H, d, J=8.4 Hz, Ar—H), 7.06 (2H, d, J=8.4 Hz, Ar—H),7.54-7.65 (5H, m, Ar—H), 7.87 (1H, s, Ar—H), 7.99 (1H, d, J=8.4 Hz,Ar—H), 8.08 (1H, s, Ar—H)

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-3-(4-hydroxy-phenyl)-propionicacid (107)

LCMS purity 90%, m/z 505 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 3.09-3.27(2H, m, CH₂), 4.03 (1H, m, CH), 4.24 (2H, s, CH₂), 4.34 (2H, s, CH₂),4.42 (2H, s, CH₂), 6.76 (2H, d J=8.3 Hz, Ar—H), 7.11 (2H, d J=8.5 Hz,Ar—H), 7.56-7.59 (5H, m, Ar—H), 7.89 (1H, s, Ar—H), 8.02 (1H, d, J=8.4Hz, Ar—H), 8.08 (1H, s, Ar—H)

(S)-3-tert-Butoxy-2-(4-{[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-butyricacid cyclopentyl ester (108)

LCMS purity 99%, m/z 568 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.20 (9H,s, 3×CH₃), 1.29 (3H, d, J=6.6 Hz, CH₃), 1.67-1.94 (8H, m, 4×CH₂), 3.75(1H, d, J=2.7 Hz, CH), 4.29-4.32 (1H, m, CH), 4.36 (4H, d, J=2.4 Hz,2×CH₂), 4.43 (2H, s, CH₂), 5.22-5.25 (1H, m, CH), 7.54-7.65 (5H, m,Ar—H), 7.88 (1H, s, Ar—H), 8.01 (1H, d, J=8.1 Hz, Ar—H), 8.08 (1H, s,Ar—H)

(S)-3-tert-Butoxy-2-(4-{[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-propionicacid cyclopentyl ester (109)

LCMS purity 95%, m/z 554 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.23 (9H,s, 3×CH₃), 1.67-1.98 (8H, m, 4×CH₂), 3.87-3.98 (2H, m, CH₂), 4.19-4.22(1H, m, CH), 4.34-4.36 (4H, m, 2×CH₂), 4.42 (2H, s, CH₂), 5.31-5.35 (1H,m, CH), 7.54-7.62 (5H, m, Ar—H), 7.87 (1H, s, Ar—H), 8.00 (1H, d, J=8.1Hz, Ar—H), 8.08 (1H, s, Ar—H)

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-4-methylsulfanyl-butyricacid cyclopentyl ester (110)

LCMS purity 90%, m/z 541 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.70-1.98(8H, m, 4×CH₂), 2.11 (3H, s, CH₃), 2.17-2.34 (2H, m, CH₂), 2.54-2.73(2H, m, CH₂), 4.19-4.23 (1H, m, CH), 4.27-4.42 (6H, m, 3×CH₂), 5.35-5.39(1H, m, CH), 7.54-7.63 (5H, m, Ar-H), 7.87 (1H, s, Ar—H), 7.97-8.00 (1H,m, Ar—H), 8.08 (1H, s, Ar—H)

(S)-1-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzyl)-pyrrolidine-2-carboxylicacid cyclopentyl ester (111)

LCMS purity 96%, m/z 508 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.66-2.29(12H, m, 6×CH₂), 3.59-3.67 (2H, m, CH₂), 4.38-4.46 (6H, m, 3×CH₂), 4.62(1H, d, J=12.3 Hz, CH), 5.21 (1H, m, CH), 7.61-7.68 (5H, m, Ar—H), 7.88(1H, s, Ar—H), 8.00-8.02 (1H, m, Ar—H), 8.13 (1H, s, Ar—H)

(S)-1-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzyl)-pyrrolidine-2-carboxylicacid (112)

LCMS purity 100%, m/z 440 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.96-2.09(2H, m, CH₂), 2.14-2.23 (2H, m, CH₂), 2.52-2.65 (1H, m, CH₂), 3.56-3.67(1H, m, CH₂), 4.19-4.25 (1H, m, CH), 4.36-4.57 (6H, m, 3×CH₂), 7.55-7.64(5H, m, Ar—H), 7.88 (1H, s, Ar—H), 7.99-8.01 (1H, m, Ar—H), 8.09 (1H, s,Ar—H)

(R)-3-tert-Butylsulfanyl-2-(4-{[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-propionicacid cyclopentyl ester(113)

LCMS purity 97%, m/z 570 [M+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.36 (9H,s), 1.79 (8H, m), 3.16 (2H, d, 5.3 Hz), 4.25 (2H, t, J=5.6 Hz), 4.31(2H, s), 4.36 (2H, s), 4.42 (2H, s), 5.34 (1H, m), 7.56 (1H, d, J=8.1Hz), 7.62 (4H, s), 7.89 (1H, s), 8.09 (1H, s), 8.51 (1H, d, J=8.1 Hz),

(R)-3-tert-Butylsulfanyl-2-(4-{[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-propionicacid (114)

LCMS purity 97%, m/z 502 [M]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.35 (9H, s,3×CH₃), 3.09 (2H, m, CH₂), 3.22 (2H, m, CH₂), 3.83 (1H, t, J=8.8 Hz,CH), 4.34 (2H, s, CH₂), 4.42 (2H, s, CH₂), 7.57 (1H, d, J=10.0 Hz, ArH),7.62 (4H, s, ArH x 4), 7.89 (1H, s, ArH), 8.02 (1H, d, J=8.1 Hz, ArH),8.09 (1H, s, ArH).

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-3,3-dimethyl-butyricacid cyclopentyl ester (115)

LCMS purity 94%, m/z 546 [M+Na]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.08 (9H,s, 3×CH₃), 1.80 (8H, m, 4×CH₂), 3.49 (1H, s, CH), 4.29 (2H, d, J=13.5Hz, CH₂), 4.29 (2H, d, J=13.5 Hz, CH₂), 4.36 (2H, s, CH₂), 4.44 (2H, s,CH₂), 5.19 (1H, t, J=5.7 Hz), 7.59 (5H, m, ArH x 5), 7.88 (1H, ArH),8.00 (1H, d, J=8.3 Hz), 8.09 (1H, s, ArH).

(S)-Cyclohexyl-(4-{[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-acetic acid cyclopentyl ester (116)

LCMS purity 100%, m/z 550 [M+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 0.86-1.95(18H, m, 9xCH₂), 3.73 (1H, m, CH), 4.11 (1H, d J=5.7 Hz, CH), 4.19 (2H,s, CH₂), 4.26 (2H, s, CH₂), 4.36 (2H, s, CH₂), 7.53 (5H, m, ArH), 7.77(1H, s, CH), 7.82 (1H, d J=11.6 Hz, ArH), 8.02 (1H, s, ArH)

(S)-Cyclohexyl-(4-{[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-aceticacid (117)

LCMS purity 100%, m/z 482 [M+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 0.72-1.60(10H, m, 9xCH₂), 3.89 (1H, m, CH), 4.11 (3H, m, CH), 4.23 (2H, s, CH₂),4.31 (2H, s, CH₂), 7.48 (5H, m, ArH), 7.76 (1H, s, CH), 7.88 (1H, dJ=11.6 Hz, ArH), 7.98 (1H, s, ArH).

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-4-methyl-pentanoicacid cyclopentyl ester (122)

LCMS purity 94%, m/z 524 [M⁺+H]⁺, 1H NMR (300 MHz, MeOD), δ: 1.01 (6H,s, 2×CH₃), 1.28 (1H, m, CH), 1.56-1.95 (10H, m, 4×CH₂, CH₂), 4.00-4.43(6H, m, 3×CH₂), 4.88 (1H, m, CH), 5.36 (1H, br s, CH), 7.47-7.62 (5H, m,ArH), 7.94 (2H, t, ArH), 8.08 (1H, s, ArH).

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-4-methyl-pentanoicacid (123)

LCMS purity 98%, m/z 456 [M⁺+H]⁺, 1H NMR (300 MHz, MeOD), δ: 1.00 (6H,m, 2×CH₃), 1.86 (2H, m, CH₂), 3.86 (1H, m, CH), 4.29 (2H, s, CH₂), 4.36(2H, s, CH₂), 4.43 (2H, s, CH₂), 7.56 (1H, m, ArH), 7.89 (1H, s, CH),8.02 (1H, d J=8.2 Hz, ArH), 8.09 (1H, s, ArH).

(S)-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-phenyl-aceticacid cyclopentyl ester (124)

LCMS purity 90%, m/z 544 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.31-1.91(10H, m, 4×CH₂, CH₂), 4.22 (2H, dd J=13.1 Hz, CH₂), 4.35 (2H, s, CH₂),4.42 (1H, s, CH₂), 5.16 (1H, s, CH), 5.30 (1H, m, CH), 7.47-7.62 (9H, m,ArH), 7.94 (2H, m, ArH), 8.08 (1H, s, ArH).

(S)-(4-{[(2-Hyd roxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-phenyl-aceticacid (125)

LCMS purity 100%, m/z 476 [M⁺+H]⁺, 1H NMR (300 MHz, MeOD), δ: 4.08-4.24(3H, m, CH, CH2), 4.35 (2H, s, CH₂), 4.43 (1H, s, CH₂), 7.46-7.75 (10H,m, ArH), 7.89 (1H, s, ArH), 8.01 (1H, d J=7.9 Hz, ArH), 8.09 (1H, s,ArH)

The following compounds were prepared according to the proceduredescribed for compound (104) and compound (105) using alternatives forstep 3 and 4 as outlined below

Step 3b: (4-Bromomethyl-benzyl)-carbamic acid tert-butyl ester

N-Bromosuccinimide (5.13 g, 28.8 mmol) was dissolved in DCM (80 mL) andcooled to 0° C. A solution of triphenylphosphine (7.18 g, 27.0 mmol) inDCM (20 mL) was prepared and added to the chilled solution followed bypyridine (1.0 mL, 1.26 mmol). Material from step 2 (2.14 g, 9.0 mmol)was dissolved in DCM (20 mL) and added and the reaction allowed to warmto r.t. and stirred for 16 h. The mixture was concentrated and theresidue purified by column chromatography (50%/50% EtOAc/heptane) toafford the desired compound (864 mg, 32%). m/z 301 [M⁺+Na]⁺

Step 4b:(S)-2-[4-(tert-Butoxycarbonylamino-methyl)-benzylamino]-propionic acidcyclopentyl ester

L-Alanine cyclopentyl ester (463 mg, 1.41 mmol) was dissolved in DMF (9mL) and to this was added DIPEA (0.74 mL, 4.24 mmol). The mixture wasstirred at r.t. for 15 min and then a solution of material from step 3b(212 mg, 0.706 mmol) in DMF (5 mL) added dropwise over 1 hr. Thereaction was then allowed to stir at r.t. for 16 hr and was then dilutedwith water (50 mL) and EtOAc (50 mL). The organic layer was washed withbrine (2×50 mL), dried and concentrated to give crude material (0.26 g,100%) which was taken to the next step without further purification. m/z377 [M⁺+Na]⁺

Steps 5-9 were as described for Compound (104) and Compound (105)

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-propionicacid cyclopentyl ester (118)

LCMS purity 95%, m/z 482 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.61 (3H,d, J=7.2 Hz, CH₃), 1.71-1.97 (8H, m, 4×CH₂), 4.13 (1H, q, J=7.2 Hz, CH),4.30 (2H, s, CH₂), 4.36 (2H, s, CH₂), 4.43 (2H, s, CH₂), 5.33-5.36 (1H,m, CH), 7.54-7.63 (5H, m, Ar—H), 7.88 (1H, s, Ar—H), 8.00 (1H, d, J=8.1Hz, Ar—H), 8.08 (1H, s, Ar—H)

(S)-2-(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-propionicacid (119)

LCMS purity 95%, m/z 414 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.64 (3H,d, J=7.1 Hz, CH₃), 4.06-4.14 (1H, m, CH), 4.31 (2H, s, CH₂), 4.36 (2H,s, CH₂), 4.43 (2H, s, CH₂), 7.55-7.63 (5H, m, Ar—H), 7.88 (1H, s, Ar—H),8.00 (1H, d, J=8.1 Hz, Ar—H), 8.09 (1H, s, Ar—H)

The following compounds were prepared according to the proceduresoutlined for compound (118) and compound (119) incorporating thefollowing alternative/additional steps

Step 4b: [4-(tert-Butoxycarbonylamino-methyl)-benzylamino]-acetic acidcyclopentyl ester

Procedure as in step 4a (using the HCl salt of the cyclopentyl ester)

Product: m/z 363 [M⁺+H]⁺

Step 4c:[[4-(tert-Butoxycarbonylamino-methyl)-benzyl]-(9H-fluoren-9-ylmethoxy-carbonyl)-amino]-aceticacid cyclopentyl ester

To a solution of[4-(tert-Butoxycarbonylamino-methyl)-benzylamino]-acetic acidcyclopentyl ester (0.2 g, 0.55 mmol) and 1 M Na₂CO₃ (1.1 mL, 1.1 mmol)in DCM (2 mL), was added slowly with stirring and ice bath cooling, asolution of 9-Fluorenylmethyl chloroformate (0.14 g, 0.55 mmol) indioxane (1.4 mL). The mixture was stirred in the ice bath for 4 h and atroom temperature overnight. The mixture was poured into water (90 mL)and extracted with diethyl ether. The organic extracts were combined,dried (MgSO₄) and evaporated to dryness to afford the desired product(0.32 g, 100%). m/z 607 [M++Na]⁺

Step 5a:[(4-Aminomethyl-benzyl)-(9H-fluoren-9-ylmethoxycarbonyl)-amino]-aceticacid cyclopentyl ester

Procedure as described in step 5.

Product m/z 485 [M⁺+H]⁺

Step 6a:{(9H-Fluoren-9-ylmethoxycarbonyl)-[4-({[2-(1-isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-benzyl]-amino}-aceticacid cyclopentyl ester

Procedure as described in step 6.

Product m/z 790 [M⁺+H]⁺

Step 7a:(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-aceticacid cyclopentyl ester (120)

{(9H-Fluoren-9-ylmethoxycarbonyl)-[4-({[2-(1-isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-benzyl]-amino}-aceticacid cyclopentyl ester (0.11 g, 0.14 mmol) was dissolved in acetonitrile(3 mL) and to it was added piperidine (1.5 mL). The resulting mixturewas stirred at room temperature for 1 h. The solvent was evaporated todryness and the product separated into 2 portions. One portion was takenthrough to hydrolysis of the cyclopentyl ester, while the second portionwas dissolved in DCM (1.5 mL) and stirred with 4M HCl in dioxane (1.0mL) for 2 h. The solvent was evaporated to dryness and the productpurified by preparative HPLC to afford the desired product as a TFAsalt. LCMS purity 99%, m/z 468 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 8.09(1H, s, ArH), 8.00 (1H, d, J=8.3 Hz, ArH), 7.88 (1H, s, ArH), 7.54-7.65(5H, m, ArH), 5.31-5.35 (1H, m, CH), 4.43 (2H, s, CH₂), 4.35 (2H, s,CH₂), 4.31 (2H, s, CH₂), 3.96 (2H, s, CH₂), 1.65-1.93 (8H, m, 4×CH₂)

Step 9a:(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-benzylamino)-aceticacid (121)

Procedure as described in step 9.

LCMS purity 99%, m/z 400 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 8.09 (1H,s, ArH), 8.00 (1H, d, J=8.3 Hz, ArH), 7.89 (1H, s, ArH), 7.54-7.62 (5H,m, ArH), 4.43 (2H, s, CH₂), 4.35 (2H, s, CH₂), 4.32 (2H, s, CH₂), 3.93(2H, s, CH₂)

Synthesis of Compounds in FIG. 8 Exemplified by Compound (126) andCompound (127)

Stage 1: 4-(tert-Butoxycarbonylamino-methyl-cyclohexanecarboxylic acid

A solution of trans-4-(aminomethyl)cyclohexane carboxylic acid (1 g, 6.4mmol) and sodium hydroxide (256 mg, 6.4 mmol) in 40 ml of dioxane and 40ml of water was cooled in an ice-water bath while stirring.Di-tert-butyl dicarbonate (1.39 g, 6.4 mmol) was added and the mixturestirred at r.t. for 5 hours and left standing overnight. The solutionwas concentrated in vacuo and acidified with 2N HCl to pH 2. Theacidified aqueous layer was extracted 3 times with EtOAc. The organiclayers were pooled and washed with brine. The organic layer was driedover magnesium sulfate and evaporated to dryness. The product wasobtained as a white solid (1.1 g, 64% yield). ¹H NMR (300 MHz, CDCl₃),δ: 0.86-1.07 (2H, m, CH₂), 1.34-1.53 (11H, m, boc and CH₂), 1.84 (2H,dd, J=13.0, 2.3 Hz, CH₂), 2.05 (2H, dd, CH₂), 2.18-2.35 (1H, m, CHCH₂),2.99 (2H, t, J=6.3 Hz, CH₂ NH), 4.59 (1H, br. s, CHCOOH), 11.0 (1H, br.s, COOH).

Stage 2: (4-Hydroxymethyl-cyclohexylmethyl)-carbamic acid tert-butylester

Lithium aluminium hydride (465 mg, 12.2 mmol) was suspended in anhydrousTHF (10 ml) and cooled down to 0° C. under N₂ atmosphere. A solution of4-(tert-butoxy-carbonyl-amino-methyl-cyclohexanecarboxylic acid (1.1 g,4.1 mmol) in THF and dioxane (10 ml, 1:1) was added slowly and themixture was stirred overnight at room temperature. Excess lithiumaluminium hydride was quenched by adding water dropwise. The cake wasfiltered and washed with THF (10 ml) and MeOH (10 ml). The filtrate wasconcentrated in vacuo and acidified with 1 N HCl to pH 2. The aqueouswas extracted twice with EtOAc. The organic layer was dried overmagnesium sulfate, filtered and evaporated to dryness to yield 964 mg ofproduct (97% yield). ¹H NMR (300 MHz, CDCl₃), δ: 0.81-1.08 (4H, m,2×CH₂), 1.33-1.60 (10H, m, boc and CH), 1.82 (4H, d, J=5.7 Hz, 2×CH₂),2.98 (2H, t, J=6.4 Hz, CH₂ NH ), 3.46 (2H, d, J=6.4 Hz, CH₂ OH), 4.60(1H, br. s, CH)

Stage 3: (4-Formyl-cyclohexylmethyl)-carbamic acid tert-butyl ester

(4-Hydroxymethyl-cyclohexylmethyl)-carbamic acid tert-butyl ester (965mg, 4.0 mmol) was dissolved in DCM (20 ml) and cooled down to −78° C.Dess Martin reagent (2.52 g, 6.0 mmol) was dissolved in DCM (30 ml) andadded slowly to the stage 2 alcohol in solution. The reaction mixturewas then stirred at r.t. for 3 h. The resulting solution was poured intoa vigorously stirred saturated NaHCO₃ and Na₂S₂O₃ solution (1:1, 100ml). The organic layer was separated and washed with brine, dried overmagnesium sulfate and evaporated to dryness to yield the product (786mg, 82% yield). ¹H NMR (300 MHz, CDCl₃), δ: 0.83-1.01 (2H, m, CH₂),1.15-1.24 (2H, m, CH₂), 1.34 (9H, s, Boc), 1.75-1.88 (2H, m, CH₂),1.90-2.00 (2H, m, CH₂), 2.05-2.18 (1H, m, CH), 2.93 (2H, t, J=6.4 Hz,CH₂ NH), 4.53 (1H, br. s, CHCHO), 9.55 (1H, s, CHO)

Stage 4:(S)-{[4-(tert-Butoxycarbonylamino-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid cyclopentyl ester

(4-Formyl-cyclohexylmethyl)-carbamic acid tert-butyl ester (390 mg, 1.6mmol) and (S)-amino-phenyl-acetic acid cyclopentyl ester (394 mg, 1.8mmol) were stirred in DCE (6 ml) at r.t. for 25 min. Acetic acid (9.6μl, 0.16 mmol) and sodium triacetoxy-borohydride (1.0 g, 4.8 mmol) wereadded and the resulting mixture was stirred for 1 h30 at r.t. DCM (10ml) and a saturated solution of NaHCO₃ (10 ml) were added and phaseswere separated. Aqueous were extracted with EtOAc (2×10 ml), theorganics were dried over magnesium sulfate, filtered and evaporated todryness. The crude product was purified by column chromatography (8:2heptane/EtOAc) to yield 223 mg of the pure amine (31% yield). LCMSpurity 100%, m/z 445 [M⁺+H]⁺.

Stage 5: (S)-[(4-Aminomethyl-cyclohexylmethyl)-amino]-phenyl-acetic acidcyclopentyl ester

(S)-{[4-(tert-Butoxycarbonylamino-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid cyclopentyl ester (223 mg, 0.5 mmol) was stirred in DCM (4 ml), TFA(1 ml) was added and the mixture was stirred at r.t, for 2 h. Thesolution was concentrated in vacuo, taken up in DCM, washed twice with asaturated solution of NaHCO₃ and once with a saturated solution ofbrine. The organic phase was dried over magnesium sulfate, filtered andevaporated to yield the expected amine as a yellow oil (130 mg, 75%yield). LCMS purity 100%, m/z 345 [M⁺+H]⁺.

Stage 6:(S)-[(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-cyclohexylmethyl)-amino]-phenyl-acetic acid cyclopentyl ester (126)

Stage 5 amine (130 mg, 0.38 mmol) was stirred with6-formyl-benzo[b]thiophene-2-carboxylic acid (1-isobutoxy-ethoxy) amide(Scheme 7) (110 mg, 0.34 mmol) in DCE for 30 min at r.t. Acetic acid(2.1 ul, 0.03 mmol) and sodium triacetoxyborohydride (218 mg, 1.0 mmol)were added and the resulting mixture was stirred overnight at r.t. Themixture was concentrated in vacuo, taken up in EtOAc, washed with asaturated solution of NaHCO₃ (10 ml) and brine (10 ml). The organicswere dried over magnesium sulfate, filtered and evaporated to dryness.The crude product (167 mg) was purified by preparative HPLC to yieldcompound (126) as a light pink solid. LCMS purity 86%, m/z 550 [M⁺+H]⁺,ca. 10% carboxylic acid. ¹H NMR (300 MHz, MeOD), δ: 1.08 (4H, m, 2×CH₂),1.76 (14H, m, 6×CH₂ and 2×CH), 2.81 (4H, m, 2×CH₂NH), 4.35 (2H, s, CH₂NH), 5.12 (1H, s, CHNH), 5.30 (1H, m, OCH), 7.51 (6H, m, Ar), 7.85 (1H,s, Ar), 7.96 (1H, d, Ar), 8.08 (1H, s, Ar).

Synthesis of((S)-[(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-cyclohexylmethyl)-amino]-phenyl-aceticacid (127)

Stage 1:(S)-{[4-(tert-Butoxycarbonylamino-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid tert-butyl ester

(4-Formyl-cyclohexylmethyl)-carbamic acid tert-butyl ester (899 mg, 3.7mmol) and (S)-teff-butyl phenylglycine ester (850 mg, 4.1 mmol) werestirred in DCE (20 ml) for 30 min. Acetic acid (20 ul, 0.37 mmol) andsodium triacetoxyborohydride (2.37 g, 11.1 mmol) were added and thereaction mixture was stirred at r.t. for 3 h. DCM (10 ml) and asaturated solution of NaHCO₃ (20 ml) were added and phases wereseparated. The aqueous phase was extracted with EtOAc (20 ml). Theorganics were dried over magnesium sulfate, filtered and concentratedunder vacuum. The crude product (2.4 g) was purified on columnchromatography (7:3 heptane I EtOAc) to yield the expected product (385mg, 24% yield). LCMS purity 100%, m/z 433 [M⁺+H]⁺.

Stage 2:(S)-{[4-(tert-Butoxycarbonylamino-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid tert-butyl ester

(S)-{[4-(tert-Butoxycarbonylamino-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid tert-butyl ester (385 mg, 0.9 mmol) was stirred in DCM (5 ml) andTFA (2 ml) was added and the mixture was stirred at r.t. for 30 min. Thesolution was concentrated in vacuo, taken up in EtOAc (5 ml), washedtwice with a saturated solution of NaHCO₃ (2×5 ml) and once with asaturated solution of brine (5 ml). The organic phase was dried overmagnesium sulfate, filtered and evaporated to yield the expected amineas a yellow oil (290 mg, 97% yield). LCMS purity 100%, m/z 333 [M⁺+H]⁺.

Stage 3:(S)-{[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid tert-butyl ester

(S)-{[4-(tert-Butoxycarbonylamino-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid tert-butyl ester (290 mg, 0.9 mmol) and6-formyl-benzo[b]thiophene-2-carboxylic acid (1-isobutoxy-ethoxy) amide(Scheme 7) (255 mg, 0.8 mmol) were stirred in DCE (8 ml) for 30 min.Acetic acid (4 ul, 0.08 mmol) and sodium triacetoxyborohydride (504 mg,2.4 mmol) were added and the reaction mixture was stirred at r.t. for 1h30. DCM (5 ml) and a saturated solution of NaHCO₃ (10 ml) were addedand phases were separated. The aqueous phase was extracted with EtOAc(15 ml). The organics were dried over magnesium sulfate, filtered andconcentrated under vacuum. The crude product (543 mg) was purified oncolumn chromatography (5 to 10% MeOH in DCM) to yield the expected pureproduct (172 mg, 34% yield). LCMS purity 100%, m/z 638 [M⁺+H]⁺.

Stage 4:(S)-{[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid tert-butyl ester (127)

(S)-{[4-({[2-(1-Isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-methyl)-cyclohexylmethyl]-amino}-phenyl-aceticacid tert-butyl ester (172 mg, 0.27 mmol) was stirred in 4M HCl indioxane solution (2 ml) at r.t. for 30 min. The solution was evaporatedto dryness to yield compound (127) as a beige solid (123 mg, 95% yield).LCMS purity 98%, m/z 482 [M⁺+H]⁺. ¹H NMR (300 MHz, MeOD), δ: 1.10 (4 H,m, 2×CH₂), 1.80 (6H, m, 2×CH₂ and 2×CH), 2.88 (2H, dd, CHZNH), 2.94 (2H,d, CH₂ NH), 4.36 (2H, s, CH₂ NH), 5.07 (1H, s, CH), 7.53 (6H, m, Ar),7.87 (1H, s, Ar), 7.97 (1H, d, Ar), 8.12 (1H, s, Ar).

The following compounds were prepared according to the proceduredescribed for Compound (126) and Compound (127)

(S)-2-[(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-cyclohexylmethyl)-amino]-4-methyl-pentanoicacid cyclopentylester (128)

LCMS purity 86%, m/z 530 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 0.99 (6H,t, J=6 Hz, 2×CH₃), 1.11 (4H, t, J=8.1 Hz, 2×CH₂), 1.76 (20H, m, 2×CH and9×CH₂), 2.80 (1H, m, CH), 2.97 (4H, m, 2×CH₂ NH), 3.95 (1H, m, CH), 4.35(2H, s, CH₂ NH), 5.32 (1H, m, OCH), 7.54 (1H, d, J=6 Hz, Ar), 7.84 (1H,s, Ar), 7.94 (1H, d, J=9 Hz, Ar), 8.08 (1H, s, Ar).

(S)-2-[(4-{[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-methyl}-cyclohexylmethyl)-amino]-4-methyl-pentanoicacid (129)

LCMS purity 95%, m/z 462 [M⁺+H]⁺, ¹H NMR (300 MHz, MeOD), δ: 1.00 (6H,t, J=6.3 Hz, 2×CH₃), 1.10 (4H, m, 2×CH₂), 1.85 (8H, m, 2×CH and3×CH₂),2.94 (4H, m, 2×CH₂ NH), 3.91 (1H, m, CHNH), 4.36 (2H, s, CH₂ NH),7.54 (1H, d, J=7.8 Hz, Ar), 7.85 (1H, s, Ar), 7.95 (1H, d, J=8.1 Hz,Ar), 8.08 (1H, s).

Synthesis of Compounds in FIG. 9 as Exemplified for Compound (130)

Stage 1: (S)-[(3-nitro-benzyl)-amino]-phenyl-acetic acid cyclopentylester

To a solution of phenylglycine cyclopentyl ester tosic acid salt (3.08g, 7.8 mmol) in DCE (120 ml) was added 3-nitrobenzaldehyde (1.01 g, 6.7mmol) then sodium triacetoxy-borohydride (3.03 g). The mixture wasstirred for 3.5 h, then quenched by addition of saturated sodiumbicarbonate solution (200 ml). Product was extracted with DCM (250 ml)and the organic extract was dried (MgSO₄). The product was carriedforward without further purification.

Stage 2: (S)-[(3-nitro-benzyl)-tert-butoxycarbonyl-amino]-phenyl-aceticacid cyclopentyl ester

To the crude mixture of (S)-[(3-nitro-benzyl)-amino]-phenyl-acetic acidcyclopentyl ester in DCM (50 ml) was added di-ter-butyl dicarbonate(3.38 g, 15.6 mmol). The mixture was heated at 50° C. overnight, thencooled to rt. N,N,N′-trimethylethylene diamine (2 ml) was then added andthe mixture stirred for 2 h. The mixture was then poured into ethylacetate (150 ml) and washed with 1 M HCl (3 times 50 ml), dried (MgSO₄)and concentrated to yield the desired product as a colourless oil (1.509g, 42% yield). LCMS purity 98%, m/z 477 (M+Na⁺). ¹H NMR (300 MHz,d6-DMSO), δ: 7.97 (1H, dd, J=2.1, 9 Hz), 7.15-7.45 (8H, m), 5.60-6.00(1H, m), 5.20-5.35 (1H, m), 4.65-4.82 (1H, m), 4.21 (1H, d, J=16 Hz),1.30-1.95 (17H, m)

Stage 3: (S)-[(3-Amino-benzyl)-tert-butoxycarbonyl-amino]-phenyl-aceticacid cyclopentyl ester

To a solution of(S)-[(3-nitro-benzyl)-tert-butoxycarbonyl-amino]-phenyl-acetic acidcyclopentyl ester (1.509 g, 3.32 mmol) in ethanol (10 ml) was addedpalladium on carbon (10%, 0.38 g, 0.36 mmol). The flask was evacuatedand back-filled with hydrogen gas. The mixture was stirred overnight,then filtered through Celite, washed with ethanol (150 ml) and thenconcentrated to yield the desire product as a colourless oil (1.351 g,96% yield). ¹H NMR (300 MHz, CDCl₃), δ: 7.19-7.42 (5H, m), 6.97 (1H, t,J=7.5 Hz), 6.46 (2H, dd, J=8.1, 16.5 Hz), 6.29 (1H, br s), 5.58 (1H, brs), 5.29 (1H, br s), 4.69 (1H, br s), 4.00 (1H, d, J=15.9 Hz), 3.74 (1H,q, J=6.9 Hz), 3.51 (2H, br s), 1.20-2.00 (17H, m)

Stage 4:(S)-[tert-Butoxycarbonyl-(3-{[2-(1-isobutoxy-ethoxycarbamoyl)-benzo[b]-thiophen-6-ylmethyl]-amino}-benzyl)-amino]-phenyl-aceticacid cyclopentyl ester

To (S)-[(3-Amino-benzyl)-tert-butoxycarbonyl-amino]-phenyl-acetic acidcyclopentyl ester (0.317 g, 0.75 mmol) was added6-Formyl-benzo[b]thiophene-2-carboxylic acid (1-isobutoxy-ethoxy)-amide(Scheme 7) (0.210 g, 0.65 mmol) in DCE (8 ml). 2 drops of glacial aceticacid were added, and then sodium triacetoxyborohydride (0.170 g, 0.8mmol). The mixture was stirred for 2 h and then poured into DCM (150ml). The solution was washed with saturated sodium bicarbonate (50 ml),then dried (MgSO₄), concentrated and purified by flash columnchromatography to yield the desired product as a pale yellow foam (0.346g, 73% yield). ¹H NMR (300 MHz, CDCl₃), δ: 8.35-8.43 (1H, m), 7.56-8.05(2H, m), 7.01-7.41 (8H, m), 6.90-7.01 (1H, m), 6.42 (1H, dd, J=2.6, 7.9Hz), 5.25-5.31 (1H, m), 5.12 (1H, q, J=5.2 Hz), 4.40 (1H, d, J=5.4 Hz),4.00 (1H, dd, J=3.1, 15.8 Hz), 3.60-3.70 (1H, m), 3.35-3.40 (1H, m),1.33-1.94 (21H, m), 0.98 (3H, d, J=6.6 Hz), 0.97 (3H, d, J=6.6 Hz)

Stage 5:(S)-{3-[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-benzyl-amino}-phenyl-aceticacid cyclopentyl ester (130)

To a solution of(S)-[tert-Butoxycarbonyl-(3-{[2-(1-isobutoxy-ethoxycarbamoyl)-benzo[b]thiophen-6-ylmethyl]-amino}-benzyl)-amino]-phenyl-aceticacid cyclopentyl ester (0.100 g, 0.14 mmol) in DCM/MeOH (1 ml:1 ml) wasadded TFA (8 ml). The solution was stirred for 2 h, then diluted withDCM (200 ml). The solution was washed with saturated sodium bicarbonate(100 ml). The solution was dried (Na₂SO₄), concentrated and purified byreverse phase HPLC to yield the desired product (8.1 mg, 11% yield).LCMS purity 98%, m/z 531 (M+H)⁺ 300 MHz, DMSO, 6:1.26-1.85 (8H, m), 3.47(2H, s), 4.21 (1H, s), 4.38 (2H, d, J=5.8 Hz), 5.02-5.07 (1H, m), 6.32(1H, t, J=6.0 Hz), 6.45 (2H, d, J=7.9 Hz), 6.57 (1H, s), 6.97 (1H, t,J=7.8 Hz), 7.23-7.35 (5H, m), 7.42 (1H, dd, J 1.2, 8.3 Hz), 7.84 (1H,s), 7.87 (1H, s), 7.93 (1H, s), 9.23 (1H, brs), 11.4 (1H, brs)

The following compounds were prepared according to the proceduresdescribed for compound (130)

(S)-{3-[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-benzylamino}-cyclohexyl-aceticacid cyclopentyl ester (131)

LCMS purity >98%, m/z 536.25 (M+H)⁺, ¹H NMR (300 MHz, d6-DMSO), δ:0.7-1.25 (8H, m), 1.50-1.95 (14H, m), 3.69 (1H, br s), 3.98 (2H, br s),4.43 (2H, br s), 5.14 (1H, t, J=5.4 Hz), 6.60-6.71 (2H, m), 7.05-7.28(3H, m), 7.43 (1H, d, J=8.5 Hz), 7.83-7.98 (2H, m), 9.25 (1H, br s),11.45 (1H, br s)

(S)-3-tert-Butoxy-2-{3-[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-benzylamino}-propionicacid cyclopentyl ester (132)

LCMS purity >98%, m/z 540.25 (M+H)⁺, ¹H NMR (300 MHz, d6-DMSO), δ: 1.05(9H, s), 1.50-1.78 (8H, m), 3.15-3.67 (5H, m), 4.38 (2H, d, J=5.8 Hz),5.05-5.15 (1H, m), 6.31 (1H, t, J=5.9 Hz), 6.40-6.48 (2H, m), 6.56 (1H,s), 6.96 (1H, t, J=7.8 Hz), 7.42 (1H, d, J=8.2 Hz), 7.87 (1H, s), 7.93(1H, s), 9.24 (1H, brs), 11.43 (1H, brs)

(S)-2-{3-[(2-Hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-benzy-lamino}-4-methyl-pentanoicacid cyclopentyl ester (133)

LCMS purity 98%, m/z 510.25 (M+H)⁺, ¹H NMR (300 MHz, d6-DMSO), δ: 0.87(6H, d, J=6.4 Hz), 1.50-1.94 (10H, m), 3.57-4.20 (3H, m), 4.44 (2H, s),5.20 (1H, t, J=5.8 Hz), 6.58-6.74 (3H, m), 7.11 (1H, t, J=7.7 Hz), 7.43(1H, d J 8.3 Hz), 7.85-7.96 (3H, m), 9.38 (2H, br s), 11.46 (1H, br s)

(S)-3-tert-Butoxy-2-{4-[(2-hydroxycarbamoyl-benzo[b]thiophen-6-ylmethyl)-amino]-benzylamino}-propionicacid cyclopentyl ester (134)

LCMS purity 98%, m/z 540.25 (M+H)⁺, ¹H NMR (300 MHz, d-4-MeOD), δ:7.64-7.77 (2H, m), 7.28 (1H, d, J=7.2 Hz), 6.99 (2H, d, J=6.6 Hz), 6.53(2H, d, J=6.6 Hz), 5.06-5.08 (1H, m), 4.35 (2H, s), 3.40-3.75 (5H, m),1.50-1.82 (8H, m), 1.04 (9H, s)

Measurement of Biological Activities Histone Deacetylase Activity

The ability of compounds to inhibit histone deacetylase activities wasmeasured using the commercially available HDAC fluorescent activityassay from Biomol. In brief, the Fluor de Lys™substrate, a lysine withan epsilon-amino acetylation, is incubated with the source of histonedeacetylase activity (HeLa nuclear extract) in the presence or absenceof inhibitor. Deacetylation of the substrate sensitises the substrate toFluor de Lys™ developer, which generates a fluorophore. Thus, incubationof the substrate with a source of HDAC activity results in an increasein signal that is diminished in the presence of an HDAC inhibitor.

Data are expressed as a percentage of the control, measured in theabsence of inhibitor, with background signal being subtracted from allsamples, as follows: —

% activity=((S ^(i) −B)/(S ^(o) −B))×100

where S^(i) is the signal in the presence of substrate, enzyme andinhibitor, S^(o) is the signal in the presence of substrate, enzyme andthe vehicle in which the inhibitor is dissolved, and B is the backgroundsignal measured in the absence of enzyme.

IC50 values were determined by non-linear regression analysis, afterfitting the results of eight data points to the equation for sigmoidaldose response with variable slope (% activity against log concentrationof compound), using Graphpad Prism software.

Histone deacetylase activity from crude nuclear extract derived fromHeLa cells was used for screening. The preparation, purchased from 4C(Seneffe, Belgium), was prepared from HeLa cells harvested whilst inexponential growth phase. The nuclear extract is prepared according toDignam JD1983 Nucl. Acid. Res. 11, 1475-1489, snap frozen in liquidnitrogen and stored at −80° C. The final buffer composition was 20 mMHepes, 100 mM KCl, 0.2 mM EDTA, 0.5 mM DTT, 0.2 mM PMSF and 20% (v/v)glycerol.

IC50 results were allocated to one of 3 ranges as follows:

Range A: IC50<100 nM,

Range B: IC50 from 101 nM to 1000 nM;

Range C: IC50>1001 nM.

NT=Not tested

Results of testing the compounds of the examples in this assay are givenin the second column of Table 2 below.

Cell Inhibition Assays

The corresponding cancer cell lines (Hela, U937 and HUT) growing in logphase were harvested and seeded at 1000 cells/well (200 ul final volume)into 96-well tissue culture plates. Following 24 h of cell growth cellswere treated with compounds (final concentration of 20 uM). Plates werethen re-incubated for a further 72 h before a sulphorhodamine B (SRB)cell viability assay was conducted according to Skehan 1990 J Nati CancInst 82, 1107-1112.

Data were expressed as a percentage inhibition of the control, measuredin the absence of inhibitor, as follows: —

% inhibition=100−((S ^(i) /S ^(o))×100)

where S^(i) is the signal in the presence of inhibitor and S^(o) is thesignal in the presence of DMSO.

IC50 values were determined by non-linear regression analysis, afterfitting the results of eight data points to the equation for sigmoidaldose response with variable slope (% activity against log concentrationof compound), using Graphpad Prism software.

IC50 results were allocated to one of 3 ranges as follows:

Range A: IC50<330 nM,

Range B: IC50 from 330 nM to 3300 nM;

Range C: IC50>3301 nM.

NT=Not tested

Results of testing the compounds of the examples in this assay are givenin the third-fifth columns of Table 2 below.

TABLE 2 Example No. HDAC Activity Hela U937 HUT 1 B C B B 2 B C B B 3 CC B C 4 B C C C 5 B B B B 6 A C C C 7 B C B B 8 B C C C 9 B B B B 10 A CC C 11 B B B B 12 B C C C 13 B C B B 14 B C C C 15 C C B B 16 C C C C 17B C B B 18 B C C C 19 B B B B 20 B B A B 21 B C C C 22 B B B B 23 B C CC 24 B C C B 25 B C C C 26 A B B B 27 B C NT NT 28 B B B B 29 B B B B 30B C NT NT 31 B B A B 32 A B NT B 33 B C NT NT 34 B B A B 35 B B B B 36 AB A B 37 B C C C 38 B NT NT NT 39 B NT A B 40 C C C C 41 C C C C 42 C BB B 43 B C C C 44 B C B B 45 C C NT NT 46 C C B B 47 B C B B 48 C C B B49 B C NT NT 50 C C B B 51 B C B B 52 C C NT NT 53 C C C C 54 C C NT NT55 C C C C 56 C C C C 57 C C NT NT 58 B B B B 59 A C NT NT 60 B B B B 61B C NT NT 62 B C C B 63 B NT NT NT 64 B B NT B 65 A C NT NT 66 B C C C67 B C NT NT 68 B C B B 69 B B NT B 70 B C NT NT 71 A B A B 72 A NT NTNT 73 A B A B 74 B NT NT NT 75 A B A A 76 A NT NT NT 77 A B A A 78 A NTNT NT 79 A NT C C 80 B NT NT NT 81 A C C B 82 B NT NT NT 83 B B B B 84 BNT NT NT 85 B C A B 86 B C A B 87 A NT NT NT 88 B B A B 89 B C A B 90 BNT NT NT 91 B C B B 92 A B B B 93 A NT NT NT 94 B NT B B 95 B NT NT NT96 B C B B 97 B NT NT NT 98 B B B B 99 C NT NT NT 100 A C B B 101 A NTNT NT 102 B C B C 103 A NT NT NT 104 B B A B 105 A NT NT NT 106 A B A A107 NT NT NT NT 108 B B B B 109 A B A B 110 A B A A 111 A A A A 112 B NTNT NT 113 B B B B 114 B NT NT NT 115 B B B B 116 B C B C 117 A NT NT NT118 A A A A 119 A NT NT NT 120 A NT A A 121 A NT NT NT 122 A B A B 123 ANT NT NT 124 B B A B 125 A NT NT NT 126 B NT A C 127 B NT NT NT 128 B BA A 129 B NT NT NT 130 C C B C 131 C C B C 132 B C B B 133 B B B C 134 BNT B C

Broken Cell Carboxyesterase Assay Preparation of Cell Extract

U937 or Hct116 tumour cells (˜10⁹ were washed in 4 volumes of DulbeccosPBS (˜1 litre) and pelleted at 1 60 g for 10 mins at 4° C. This wasrepeated twice and the final cell pellet was then resuspended in 35 mlof cold homogenising buffer (Trizma 10 mM , NaCl 130 mM, CaCl₂ 0.5 mM PH7.0) at 25° C. Homogenates were prepared by nitrogen cavitation (700 psifor 50 min at 4° C.). The homogenate was kept on ice and supplementedwith a cocktail of inhibitors designed to give final concentrations of

Leupeptin 1 μM Aprotinin 0.1 μM E64 8 μM Pepstatin 1.5 μM Bestatin 162μM Chymostatin 33 μM

After clarification of the cell homogenate by centrifugation at 360 rpmfor 10 min, the resulting supernatant was used as a source of esteraseactivity and could be stored at −80° C. until required.

Measurement of Ester Cleavage

Hydrolysis of ester to the corresponding carboxylic acid can be measuredusing this cell extract. To this effect cell extract (˜30 ug/total assayvolume of 0.5 ml) was incubated at 37° C. in a Tris-HCl 25 mM, 125 mMNaCl, buffer, PH 7.5 at 25° C. At zero time the relevant ester(substrate), at a final concentration of 2.5CM was then added andsamples incubated at 37° C. for the appropriate time (Usually zero or 80minutes). Reactions were stopped by the addition of 3× volumes ofAcetonitrile. For zero time samples the acetonitrile was added prior tothe ester compound. After centrifugation at 12000 g for 5 minutes,samples were analysed for the parent ester and its correspondingcarboxylic acid at room temperature by LCMS (Sciex API 3000, HP100binary pump, CTC PAL). Chromatographic conditions used were based on anAceCN (75*2.1 mm) column and a mobile phase of 5-95% acetonitrile inwater /0.1% formic acid.

1-47. (canceled)
 48. A compound of formula (I) or a salt, N-oxide,hydrate or solvate thereof:

wherein R₁ is a carboxylic acid group (—COOH), or an ester group whichis hydrolysable by one or more intracellular carboxyesterase enzymes toa carboxylic acid group; R₂ is the side chain of a natural ornon-natural alpha amino acid; Y is a bond, —C(═O)—, —S(═O)₂—, —C(═O)O—,—C(═O)NR₃—, —C(═S)—NR₃, —C(═NH)NR₃ or —S(═O)₂NR₃— wherein R₃ is hydrogenor optionally substituted C₁-C₆ alkyl; L¹ is a divalent radical offormula (Alk¹)_(m)(Q)_(n)(Alk²)_(p)— wherein m, n and p areindependently 0 or 1, Q is (i) an optionally substituted divalent mono-or bicyclic carbocyclic or heterocyclic radical having 5-13 ringmembers, or (ii), in the case where both m and p are 0, a divalentradical of formula —X²-Q¹- or -Q¹X²— wherein X² is —O—, S— or NR^(A)—wherein R^(A) is hydrogen or optionally substituted C₁-C₃ alkyl, and Q¹is an optionally substituted divalent mono- or bicyclic carbocyclic orheterocyclic radical having 5-13 ring members, Alk¹ and Alk²independently represent optionally substituted divalent C₃-C₇ cycloalkylradicals, or optionally substituted straight or branched, C₁-C₆alkylene, C₂-C₆ alkenylene , or C₂-C₆ alkynylene radicals which mayoptionally contain or terminate in an ether (—O—), thioether (—S—) oramino (—NR^(A)—) link wherein R^(A) is hydrogen or optionallysubstituted C₁-C₃ alkyl; X¹ represents a bond; —C(═O); or —S(═O)₂—;—NR₄C(═O)—, —C(═O)NR₄—, —NR₄C(═O)NR₅—, —NR₄S(═O)₂—, or —S(═O)₂NR₄—wherein R₄ and R₅ are independently hydrogen or optionally substitutedC₁-C₆ alkyl; z is 0 or 1; A represents an optionally substituted mono-,bi- or tri-cyclic carbocyclic or heterocyclic ring system wherein theradicals R₁R₂NH—Y-L¹-X¹-[CH₂],- and HONHCO-[LINKER]- are attacheddifferent ring atoms; and -[Linker]- represents a divalent linkerradical of formula —(CH₂)_(x)-Z-L²- linking a ring atom in A with thehydroxamic acid group CONHOH, wherein x is 0 or 1; Z is a bond,—NR₃C(═O)—, —C(═O)NR₃—, —NR₄C(═O)—NR₃—, —C(═S)—NR₃,—C(═NH)—NR₃—NR₃S(═O)₂—, or —S(═O)₂NR₃— wherein R₃ is hydrogen or C₁-C₆alkyl; —C(═O); or —S(═O)₂—; and L² represents an optionally substituted,straight or branched, C₄-C₇ alkylene, C₄-C₆ alkenylene or C₄-C₆alkynylene radical which may optionally contain or terminate in an ether(—O—), thioether (—S—) or amino (—NR^(A)—) link wherein R^(A) ishydrogen or optionally substituted C₁-C₃ alkyl.
 49. A compound asclaimed in claim 48 wherein, in the -[Linker]- radical, x is 0, Z is—C(═O)—, —NHC(═O)— or —C(═O)NH— and L² is —CH₂)₅—, —(CH₂)₆—, or—(CH₂)₇—.
 50. A compound as claimed in claim 48 wherein A is one of thefollowing, optionally substituted:

wherein R₁₀ is hydrogen or optionally substituted C₁-C₆ alkyl, the bondintersected by the wavy lines shown as connected to a fixed atomconnects to the Linker radical in the compounds (I), and the other bondshown as floating links any convenient ring atom of the ring systemshown to the grouping R₁R₂CHNHYL¹X¹[CH2]_(z)—.
 51. A compound as claimedin claim 48 wherein A is a 1,2-phenylene, 1,3-phenylene or 1,4-phenyleneradical.
 52. A compound as claimed in claim 48 wherein z is
 0. 53. Acompound as claimed in claim 48 wherein Y is a bond.
 54. A compound asclaimed in claim 48 wherein, in the radical L¹, Alk¹ and Alk², whenpresent, are selected from —CH₂—, —CH₂CH₂—, —CH₂CH₂CH₂—, and divalentcyclopropyl, cyclopentyl and cyclohexyl radicals.
 55. A compound asclaim 48 wherein, in the radical L¹, Q is a divalent phenyl radical or amono-, or bi-cyclic heteroaryl radical having 5 to 13 ring members, 56.A compound as claimed in claim 48 wherein, in the radical L¹, m and pare 0; or n and p are 0 and m is 1; or m, n and p are all
 0. 57. Acompound as claimed in claim 48 wherein the radical —Y-L¹-X¹-[CH₂]_(z)—is selected from —C(═O)—, —C(═O)NH—, —(CH₂)_(v)—, —(CH₂)_(v)O—,—C(═O)—(CH₂)_(v)—, —C(═O)—(CH₂)_(v)O—, —C(═O)—NH—(CH₂)_(w)—,—C(═O)—NH—(CH₂)_(w)O—

wherein v is 1, 2, 3 or 4 and w is 1, 2 or
 3. 58. A compound as claimedin claim 48 wherein the radical Y-L¹-X¹-[CH₂]_(z)—, is —CH₂—, —CH₂O—,—C(═O)—CH₂—, —C(═O)—CH₂O—, —C(═O)—NH—CH₂—, or —C(═O)—NH—CH₂O—.
 59. Acompound as claimed in claim 48 wherein R₁ is an ester group of formula—(C═O)OR₉ wherein R₉ is (i) R₇R₈CH— wherein R₇ is optionally substituted(C₁-C₃)alkyl-(Z¹)_(a)-(C₁-C₃)alkyl- or(C₂-C₃)alkenyl-(Z¹)_(a)-(C₁-C₃)alkyl- wherein a is 0 or 1 and Z¹ is —O—,—S—, or —NH—, and R₈ is hydrogen or (C₁-C₃)alkyl- or R₇ and R₈ takentogether with the carbon to which they are attached form an optionallysubstituted C₃-C₇ cycloalkyl ring or an optionally substitutedheterocyclic ring of 5- or 6-ring atoms; or (ii) optionally substitutedphenyl or monocyclic heterocyclic having 5 or 6 ring atoms,
 60. Acompound as claimed in claim 59 wherein R₉ is methyl, ethyl, n- oriso-propyl, n- or sec-butyl, cyclohexyl, allyl, phenyl, benzyl, 2-, 3-or 4-pyridylmethyl, N-methylpiperidin-4-yl, tetrahydrofuran-3-yl ormethoxyethyl.
 61. A compound as claimed in claim 59 wherein R₉ iscyclopentyl.
 62. A compound as claimed in claim 48 wherein R₂ iscyclohexylmethyl, cyclohexyl, pyridin-3-ylmethyl, sec-butyl, tert-butyl,1-benzylthio-1-methylethyl, 1-methylthio-1-methylethyl, or1-mercapto-1-methylethyl.
 63. A compound as claimed in claim 48 whereinR₂ is phenyl, benzyl, phenylethyl, tert-butoxymethyl or iso-butyl.
 64. Acompound as claimed in claim 48 wherein R₁ is a carboxylic acid group(—COOH), or an ester group an ester group of formula —(C═O)OR₉ whereinR₉ is methyl, ethyl, n- or iso-propyl, n- or sec-butyl, cyclopentyl,cyclohexyl, allyl, phenyl, benzyl, 2-, 3- or 4-pyridylmethyl,N-methylpiperidin-4-yl, tetrahydrofuran-3-yl or methoxyethyl; R₂ iscyclohexylmethyl, cyclohexyl, pyridin-3-ylmethyl, sec-butyl, tert-butyl,1-benzylthio-1-methylethyl, 1-methylthio-1-methylethyl,1-mercapto-1-methylethyl. phenyl, benzyl, phenylethyl, tert-butoxymethylor iso-butyl; the radical —Y-L¹-X¹-[CH₂]_(z)—, is —CH₂—, —CH₂O—,—C(═O)—CH₂—, —C(═O)—CH₂O—, —C(═O)—NH—CH₂—, or —C(═O)—NH—CH₂O—; Arepresents a 1,3-phenylene, 1,3-phenylene or 1,4-phenylene radical; and-[Linker]- represents a divalent radical of formula —(CH₂)_(x)-Z-L²-wherein x is 0, Z is —C(═O)—, —NHC(═O)— or —C(═O)NH—, and L² is—(CH₂)₅—, —(CH₂)₆—, or —(CH₂)₇—;
 65. A compound as claimed in claim 48selected from the group consisting of(S)-3-tert-Butoxy-2-[3-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-propionicacid cyclopentyl ester,(S)-2-{3-[3-(7-Hydroxycarbamoyl-heptanoylamino)-phenoxy]-propylamino}-3-phenyl-propionicacid cyclopentyl ester,(S)-3-tert-Butoxy-2-[4-(7-hydroxycarbamoyl-heptanoylamino)-benzylamino]-propionicacid cyclopentyl ester,(S)-[4-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid cyclopentyl ester,(S)-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-phenyl-aceticacid cyclopentyl ester,(S)-2-[3-(7-Hydroxycarbamoyl-heptanoylamino)-benzylamino]-4-methyl-pentanoicacid cyclopentyl ester, and pharmaceutically acceptable salts, hydratesand solvates thereof.
 66. A pharmaceutical composition comprising acompound as claimed in claim 48, together with a pharmaceuticallyacceptable carrier.
 67. A method for the treatment of cell-proliferationdisease, polyglutamine disease, neurodegenerative disease, autoimmunedisease, inflammatory disease, organ transplant rejection, diabetes,haematological disorders and infection, which comprises administering toa subject suffering such disease an effective amount of a compound offormula (I) as claimed in claim
 48. 68. A method as claimed in claim 67for the treatment of cancer cell proliferation, Huntingdon disease, orAlzheimer disease.
 69. A method as claimed in claim 67 for the treatmentof rheumatoid arthritis.
 70. A pharmaceutical composition as claimed inclaim 66 which is adapted for topical administration and wherein R₂ islinked to the carbon atom to which it is attached through a methyleneradical CH₂—.
 71. A compound of formula (I) or a salt, N-oxide, hydrateor solvate thereof:

wherein R₁ is a carboxylic acid group (—COOH), or an ester group whichis hydrolysable by one or more intracellular carboxyesterase enzymes toa carboxylic acid group; R₂ is the side chain of a natural ornon-natural alpha amino acid; Y is a bond, —C(═O)—, —S(═O)₂—, —C(═O)O—,—C(═O)NR₃—, —C(═S)—NR₃, —C(═NH)NR₃ or —S(═O)₂NR₃— wherein R₃ is hydrogenor optionally substituted C₁-C₆ alkyl; L¹ is a divalent radical offormula -(Alk¹)_(m)(Q)_(n)(Alk²)_(p)— wherein m, n and p areindependently 0 or 1, Q is (i) an optionally substituted divalent mono-or bicyclic carbocyclic or heterocyclic radical having 5-13 ringmembers, or (ii), in the case where both m and p are 0, a divalentradical of formula —X²-Q¹- or -Q¹-X²- wherein X² is —O—, S— or NR^(A)—wherein R^(A) is hydrogen or optionally substituted C₁-C₃ alkyl, and Q¹is an optionally substituted divalent mono- or bicyclic carbocyclic orheterocyclic radical having 5-13 ring members, Alk¹ and Alk²independently represent optionally substituted divalent C₃-C₇ cycloalkylradicals, or optionally substituted straight or branched, C₁-C₆alkylene, C₂-C₆ alkenylene, or C₂-C₆ alkynylene radicals which mayoptionally contain or terminate in an ether (—O—), thioether (—S—) oramino (—NRA—) link wherein R^(A) is hydrogen or optionally substitutedC₁-C₃ alkyl; X¹ represents a bond; —C(═O); or —S(═O)₂—; —NR₄C(═O)—,—C(═O)NR₄—, —NR₄C(═O)NR₅—, —NR₄S(═O)₂—, or —S(═O)₂NR₄— wherein R₄ and R₅are independently hydrogen or optionally substituted C₁-C₆ alkyl; z is 0or 1; A represents an optionally substituted mono-, bi- or tri-cycliccarbocyclic or heterocyclic ring system wherein the radicalsR₁R₂NH—Y-L¹-X¹—[CH₂]_(z)— and HONHCO-[LINKER]- are attached differentring atoms; and -[Linker]- represents a divalent radical of formula—(CH₂)_(n)-L³-Ar¹-L⁴- wherein x is 0 or 1; L³ is Z or L² or Z-L² whereinZ is as defined in claim 1 and L² is a bond or an optionally substituteddivalent C₁-C₃ alkylene radical; Ar¹ is a divalent phenyl radical or adivalent mono-, or bi-cyclic heteroaryl radical having 5 to 13 ringmembers, and L⁴ is a bond or optionally substituted —CH₂— or —CH═CH—,72. A compound of formula (I) or a salt, N-oxide, hydrate or solvatethereof:

wherein R₁ is a carboxylic acid group (—COOH), or an ester group whichis hydrolysable by one or more intracellular carboxyesterase enzymes toa carboxylic acid group; R₂ is the side chain of a natural ornon-natural alpha amino acid; Y is a bond, —C(═O)—, —S(═O)₂—, —C(═O)O—,—C(═O)NR₃—, —C(═S)—NR₃, —C(═NH)NR₃ or —S(═O)₂NR₃— wherein R₃ is hydrogenor optionally substituted C₁-C₆ alkyl; L¹ is a divalent radical offormula -(Alk¹)_(m)(Q)_(n)(Alk²)_(p)— wherein m, n and p areindependently 0 or 1, Q is (i) an optionally substituted divalent mono-or bicyclic carbocyclic or heterocyclic radical having 5-13 ringmembers, or (ii), in the case where both m and p are 0, a divalentradical of formula —X²-Q¹- or¹-QX²- wherein X² is —O—, S— or NR^(A)—wherein R^(A) is hydrogen or optionally substituted C₁-C₃ alkyl, and Q¹is an optionally substituted divalent mono- or bicyclic carbocyclic orheterocyclic radical having 5-13 ring members, Alk¹ and Alk²independently represent optionally substituted divalent C₃-C₇ cycloalkylradicals, or optionally substituted straight or branched, C₁-C₆alkylene, C₂-C₆ alkenylene, or C₂-C₆ alkynylene radicals which mayoptionally contain or terminate in an ether (—O—), thioether (—S—) oramino (—NR^(A)—) link wherein R^(A) is hydrogen or optionallysubstituted C₁-C₃ alkyl; X¹ represents a bond; —C(═O); or —S(═O)₂—;—NR₄C(═O)—, —C(═O)NR₄—, —NR₄C(═O)NR₅—, —NR₄S(═O)₂—, or —S(═O)₂NR₄—wherein R₄ and R₅ are independently hydrogen or optionally substitutedC₁-C₆ alkyl; z is 0 or 1; A represents an optionally substituted mono-,bi- or tri-cyclic carbocyclic or heterocyclic ring system wherein theradicals R₁R₂NH—Y-L¹-X¹—[CH₂]_(z)— and HONHCO-[LINKER]- are attacheddifferent ring atoms; and -[Linker]- represents a divalent radical offormula —(CH₂)_(x)-L³-B—Ar¹-L⁴- wherein x is 0 or 1; L³ is Z or L² orZ-L² wherein Z is as defined in claim 1 and L² is a bond or anoptionally substituted divalent C₁-C₃ alkylene radical;; Ar¹ is adivalent phenyl radical or a divalent mono-, or bi-cyclic heteroarylradical having 5 to 13 ring members, and L⁴ is a bond or optionallysubstituted —CH₂— or —CH═CH—, and B is a mono- or bi-cyclic heterocyclicring system.